Pyrodigital Consultant’s Phase III Firing System is a Professional Level Tool. This tool is an integrated hardware system which provides a means in which to fire industry standard pyrotechnic squibs under the control of a dedicated personal computer, the Pyrodigital Field Controller, or other Pyrodigital Phase III Controller.
Pyrodigital Consultant’s Phase III Firing System as a Professional Level Tool is designed, intended, and only to be used by Professional Pyrotechnic Operators in a controlled Professional Environment permitted by the Fire Authority having jurisdiction, in conjunction with Class C or Class B explosives ONLY that have been examined and issued Federal EX numbers by the US Department of Transportation. The Pyrodigital Firing System is not designed nor shall be used to ignite any Class A explosive.
The Phase III System can be divided into two major components, The SYSTEM CONTROLLER and the SYSTEM NETWORK.
The SYSTEM CONTROLLER is what Controls the operation of the Phase III SYSTEM NETWORK. This Controller is at the Control Location, at the point where the operator controls the Fireworks Display or Special Effects. The System Controller can be either 1) The Pyrodigital Field Controller, 2) another type of Pyrodigital Phase III Controller, or 3) the Pyrodigital Interface Box connected to a Personal Computer.
The SYSTEM NETWORK is composed of the Firing Modules, the Interconnecting Cables, and the Splitter Boxes. This Network originates at the System Controller via the single main Interconnecting Cable that is connected to the System Controller. This main Interconnecting Cable then goes to the first Splitter Box which is then connected with additional Interconnecting Cables to the Firing Modules. One (or more) of these Interconnecting Cables can also go to additional Splitter Box(s) via more Interconnecting Cables to which additional Firing Modules are connected.
The System Network may be also referred to as the Firing Network or simply the Network in various places in this manual. Likewise, the System Controller may sometimes be referred to as simply the Controller.
The Phase III system is built around the modular concept. Firing Modules form the basic building blocks of the System Network and may be added as needed (with associated interconnecting Cables and Splitter Boxes). This approach allows for maximum flexibility in both physical Layout of the System Network and the overall size (or capacity) of the entire system.
In usage a single (one) interconnecting cable runs from the firing control location out to the firing site. This cable is connected to a splitter box (or to a single firing module). Interconnecting cables then leave the splitter box and connect to either a firing module, or to another splitter box. All firing modules thus, are then eventually connected into the communications network. See this manual Sections on Interconnecting Cables, Splitter Boxes, and System Layout.
Splitting of the signal (via the interconnecting cables and splitter boxes) can be done as many times as needed and need not follow a logical array. A logical layout of splits (primary, secondary, etc.) however, may be beneficial in a complicated large layout for simplicity and checking. Also see this manual Section on System Layout, the diagrams on possible System Layouts.
Since the squib firing power is sent through the interconnecting cable, this limits the total system expansion to the load to be fired. Normally there would be sufficient power to fire several squibs on one circuit and one would not be concerned over sufficient firing current. Electrical resistance specifications should be checked to insure sufficient squib firing power whenever very long squib extension wires are used, when firing many squibs per circuit, or when many interconnecting cables (in the direct path) are used to connect a firing module. See the Manual section; Squib Firing Power, Maximum Limits.
The Phase III system is physically laid out and all the firing modules are connected via the interconnecting cables and splitter boxes. The correct module address is set via the rotary thumbwheel address switch. The system may then be powered up to check for proper communications to all the firing modules, with all firing modules shunted. The pyrotechnic devices are then connected via the squib legwires to the firing modules. The correct device must, of course, be connected to the correct location of the correctly addressed firing module. Squib status may be checked when all the squibs are connected in the “status” mode. (after lifting the shunts on the firing modules when the firing area is clear) Last minute changes to the data table may be made if necessary, such as changes due to different shells on location than planned for, changes in address/shot code, and changes in choreography (See this manual section on System Check-Out).
When Operating the System in a Pyromusical Display Situation, when ready, the system is armed and the System Controller is placed in the Auto Fire or Smart Fire mode. In this mode, the Controller quickly generates an internal firing data table. This firing table is the table from which the actual firing commands are issued. This table has two entries per cue being; 1) the actual firing time , which is the event time minus the pre fire delay, and 2) the address/shot code for that event. The system fires all the squibs (events/cues) according to the firing table time (with the associated address/shot code) against the time code input.
The time code input comes from a feed line off the time track of the master audio tape as it is played (from which the display was originally choreographed and programmed to). The music on the other tracks of the master tape machine is radio broadcast or drives a P A System , or both. This time code feed may be a direct connection to the tape machine (when the music is played on location), may travel over phone lines (from the radio station to the firing control location as an example), or over special radio links (from the P A mixing console as an example). On location audio synchronization of two identical music tracks, with the slave machine outputting time code to the computer, is possible, however less desirable and not as precise. Please see the section of this Manual on Time Code for further detail.
The time code input is provided to the Field Controller as a high impedance line level signal for connection to the RCA play input jack. The Field Controller will switch to internal time drive mode if the time code signal is lost. This will only happen after the Field Controller has received at least one valid time code, and the Field Controller will continue on internal time drive (same crystal reference which generated original time code) until it receives a new valid time code. This automatic switching prevents the display from stopping should the time code data line be intermittent or terminated once the display is started. The operator can always override this feature by stopping the Field Controller.
The Firing Module is the final link which connects the squib to the Phase III System. The squib, of course, is connected to (in contact with) the Pyrotechnic Device to be ignited under control of the Phase III System.
The firing module is a small aluminum box which houses various electronic components. Basically the firing module takes input control signals and outputs firing power to the desired squib. The firing module is intended to be near the devices to be fired and thus has various output termination options. Output termination options means the various ways in which the squib may be connected to the firing module, or thus terminated. (Note: squib may mean more than 1 squib per circuit)
Each type of firing module is electrically identical and only varies physically to accommodate different ways in which to connect the squib. Firing modules are therefore completely interchangeable anywhere within the physical layout.
Since the firing modules are electrically identical and interchangeable, the question then is how are the modules distinguished from one another? This is accomplished by a double hex rotary thumbwheel address switch on each module (see the manual section on hexadecimal for further explanation of hex). The thumbwheel switch is externally accessible and a firing module address may be selected in a matter of seconds. This means that any firing module may be positioned anywhere within the physical layout and then simply set to the correct address. The address usage is more fully covered in the ADDRESS Section of this Manual.
Each type firing module has 16 firing circuits. The module type (output termination options) dictates the manner in which the squib is connected to each of the 16 circuits. Each and every squib therefore has a specific module address and a shot address, or the location of a particular squib on that particular module. This address / shot code is the information which the computer uses to talk to a specific squib. Up to 128 module addresses times 16 shots per module gives up to 2048 individually addressable firing circuits (See ADDRESS Section of this Manual).
The Firing module also houses an input connector of the 3 wire XLR professional series. The 3 wire interconnecting cable is thus connected to the module via this connector.
For safety and operational purposes the firing module also has a rotary shunting switch. This is a 2 position switch, being either shunted or armed (unshunted). In the shunted position all firing power outputs are disconnected and all 16 squib connectors (output termination options) are individually short circuited together (shunted). The module electronics, however, are still operative and the entire system may be powered up for check out in complete safety and in a non fire condition with all squibs shunted. Successful operation and communication within the entire layout of the system at this point (shunted) indicates that all is OK and it is safe to proceed.
The firing modules also have provisions for sending squib continuity information back to the computer. With the shunts opened the entire layout may then be checked to insure all the squibs are connected and ready to fire.
PLEASE SEE THE ACCOMPANYING DRAWING WHICH INDICATES THE RESPECTIVE CONTROLS, INPUTS, AND OUTPUTS OF THE FIRING MODULE.
*****DRAWINGS OF FIRING MODULES, 2 EACH
The Splitter Box is a simple mechanical housing containing 1 (one) male XLR input connector and a number of female XLR output connectors. The Splitter Boxes simply serve to expand the number of Firing Modules which may be connected to the System Network. Splitter Boxes may also be in the form of a “Y” connector, with one input (male XLR) and 2 outputs (female XLR). Even though this is not technically a “box” it is still called a Splitter Box.
The Splitter Boxes are available in various sizes which are determined by the number of outputs, or female XLR chassis connectors. There is only 1 input, being a male XLR chassis connector. The Splitter Box is a simple mechanical unit and contains no electronics. The Splitter box XLR input connector is simply hardwired in parallel to all the output connectors, pin 1 to 1, 2 to 2, and 3 to 3.
The female XLR connectors have a locking device which firmly locks in the corresponding male XLR connector on the Interconnecting Cable. Inserting the male XLR connector on the Interconnecting Cable fully into the female chassis connector on the Splitter Box automatically locks the connector in place. Simply push in on the latch to release the Interconnecting Cable.
The Splitter Box serves to expand the number of Firing Modules which may be connected to the Phase III System. Without a Splitter Box only one Firing Module could be connected to the main Interconnecting Cable.
ALL OF THE FEMALE XLR OUTPUTS ON THE SPLITTER BOXES NEED NOT BE USED. Depending on the size of the System (the number of Firing Modules), there may be one or more Splitter Boxes which may have several outputs unused on each Splitter Box. This is perfectly acceptable and normal.
Each Phase III Firing Module can fire more than 1 squib on EACH of it’s 16 circuits. Calculating the maximum number of squibs, the maximum length of Interconnecting Cables, or the maximum squib extension wire lengths which may be used is simple and straightforward. Such calculation eliminates any uncertainty or need for test firings.
The key to simple calculation is Rmax. Rmax represents the maximum allowable resistance which may be added to the firing circuit. Those resistance elements added to the firing circuit are 1) the Interconnecting Cables, 2) the squib(s), and 3) any squib extension wires. If the sum of these 3 resistances is below Rmax then the squib(s) will fire reliably. Resistances as follows;
1) INTERCONNECTING CABLES; This resistance is the sum of the resistances of all the Interconnecting Cables IN THE DIRECT PATH between the Interface Box (or Pyrodigital Field Controller) and the Firing Module in question. This is NOT the sum of the resistances of all the Interconnecting Cables, but only those Cables in which the squib firing power travels through to get from the Interface Box (or Field Controller) to the one particular Firing Module being addressed to fire. This value will be the same for each Firing Module unless one or more Firing Modules are on longer Interconnecting Cables or have been sub Split and are connected with additional Interconnecting Cables (and Splitter Boxes).
2) SQUIBS; This resistance is the sum of the resistances of the actual squib(s) to be used. PYRODIGITAL CONSULTANTS RECOMMENDS SINGLE SERIES CONNECTION ONLY. Series connections always work reliably because the bridgewire within the squib match head achieves the match composition ignition temperature long before the temperature required to melt the bridgewire. This means all the squibs will be ignited before the series circuit is broken. This also means that ALL THE SQUIBS WITHIN THE SERIES MUST BE OF THE SAME TYPE AND MANUFACTURE.
Single series connection makes continuity checks easier as parallel connections can show continuity with one or more squibs not actually connected. Parallel squib connections also do not provide any increase in the number of squibs which may be fired and usually reduce the number due to the limited current available. Double series connections (2 parallel series) may increase the number of squibs slightly.
3) SQUIB EXTENSION WIRES; If squib(s) are extended with additional wire the resistance of the extension wire must be added.
Note: DO NOT attempt to simultaneously fire squibs on different Firing Modules by selecting identical Firing Module Addresses. This will reduce the squib firing power available (firing power parallel split and potentially unbalanced) and also create problems for the Interface Box to understand multiple Squib Status Returns. Refer to the Section of this Manual on SAME ADDRESS FIRING ON DIFFERENT FIRING MODULES – MULTIPLE SHOTS
Rmax >= Resistance of;[Interconnecting Cables + Squib(s) + Extension Wire]
Single Squib Rmax = 45.0 ohm – Single Series Rmax = 13.67 ohm
INTERCONNECTING CABLES* COPPER WIRE RESISTANCE (ohms/1000’, awg)
Pink Cable (ST) 2.2O ohms/100’ No. 8 0.628
20 gauge Hypalon (HP) 1.54 ohms/100’ No. 10 0.999
16 gauge Hypalon (SHP) 0.63 ohms/100’ No. 12 1.59
No. 14 – – – – – 2.53
No. 16 4.02
SQUIB RESISTANCE – Common squibs, nominal No. 18 6.38
No. 20 10.15
Davey Fire = 1.9 ohms w/ 6’ legwires No. 21 – – – – – 12.80
ICI = 1.6 ohms w/ 6’ legwires No. 22 16.14
Atlas = 1.6 ohms w/ 6’ legwires No. 23 20.36
(Staticmaster) = 1.2 ohms w/ 6’ legwires No. 24 25.67
*For non standard or different lengths of Interconnecting Cable simply calculate it’s Effective Total Resistance (the sum of 1 conductor plus the shield for the length of the Cable) Example; A 250 foot section of the 16 gauge Hypalon Cable would have a resistance of 2.5 times the 100 foot length specification = 1.58 ohms.; or 750 feet of 20 gauge Hypalon = 750 x 1.54 ohms/100’ (divided by 100’) = 11.55 ohms
EXAMPLE: 256 shot Phase III System, 16 Firing Modules; HP-100 Interconnecting Cable (Interface Box to SPL-16 Splitter Box); 16 ea HP-50 Interconnecting Cables (Splitter Box to Firing Modules), Davey Fire 6’ (2 meter) squibs.
What is maximum # of squibs which can be fired on each of the 256 circuits?
13.67 >= [1.54 ohm (HP-100) + 0.77 ohm (HP-50)] + Resistance Squibs Single Series + 0 ohms
11.36 >= Resistance Squibs in Single Series
11.36 >= 6 squibs x 1.9 ohms ea Davey Fire Squibs
11.36 >= 11.40 @ FALSE but so close (0.04 ohm); 6 squibs = OK MAXIMUM
The Phase III System in the above example is expanded to 304 shots by adding 3 Firing Modules. One of the 16 HP-50 Cables from the SPL-16 Splitter is replaced by a HP-100 Cable which goes to a SPL-05 Splitter. 3 HP-50 Cables go to the new Firing Modules from the added SPL-05 Splitter. It is desired to fire a set piece with 3 ICI squibs simultaneously 200 feet away from one of the new Firing Modules.
Rmax >= Resistance of;
Interconnecting Cables + Res Squib(s) + Res Extension Wires
13.67 >= [1.54 + 1.54 + 0.77] + [3 x 1.6] +[2 wire x (200’ x 10.15 ohm/1000’)]
13.67 >= 12.71 @ TRUE, this arrangement fire OK
INTERFACE BOX, IB (or Field Controller)
26.5 vdc – Power Supply*
1.5 vdc – Insertion Loss
0 ohm – Added Resistance
4 amp – Maximum Power (current limited)
*if using external battery input use it’s actual voltage
Single Squib 0.5 amp
Single Series 1.5 amp
Parallel/Series 1.5 amps/series
Straight Parallel 1.0 amp/squib
FIRING MODULES, FM – 1.5 vdc Insertion Loss, 2.0 ohm Added Resistance
Max. Voltage Avail. = 23.5 vdc (26.5 vdc – 1.5 vdc IB Loss – 1.5 vdc FM Loss)
Max. Current Avail. = 4 amps, less load of Firing Modules – 0.004 amp/FM
Rmax = The maximum added resistance allowed while still being above the minimum recommended squib firing current. The effects of the Interface Box, the Firing Modules, and the Splitter Boxes have been compensated for in calculating Rmax. The calculations are straightforward using Ohms Law, R = V / I.
Single Squib Rmax = 45.0 ohm = 23.5 vdc/0.5 amp – 2.0 ohm FM Resis.
Single Series Rmax = 13.67 ohm = 23.5 vdc/1.5 amps – 2.0 ohm FM Resis.
Dbl Series/Parallel Rmax = 5.83 ohm = 23.5 vdc/3.0 amps – 2.0 ohm FM
1.5 amps per series x 2 series = 3.0 amps required
Triple Series/Parallel Rmax = Not Advisable – 4.5 amps > Max. Current
1.5 amps per series x 3 series = 4.5 amps required
Straight Parallel Rmax = 3.88 ohm = 23.5 vdc/4.0 amps – 2.0 ohm FM Res
maximum avail = 4.0 amps = 4 squibs x 1 amp/squib = 4.0 amps required
MAXIMUM SQUIB FIRING POWER – BEYOND THE DESIGN SPECIFICATIONS
It has been observed, tested, and reliably proved that many more squibs can be Fired, per event, than indicated based on the design specification. Those specifications were based on conservative specifications from the Blasting Industry for the use of Electric Blasting Caps (EBC’s, of which the squib is the initial initiator). Pyrodigital Consultants and others have tested and successfully Fired Displays with many squibs in series on long runs of extension (scab) wire through one thousand plus feet of Interconnecting Cable.
PYRODIGITAL CONSULTANTS CAN MAKE NO SPECIFIC ENDORSEMENTS CONCERNING FIRING RELIABILITY WHEN USING PHASE III BEYOND IT’S DESIGN SPECIFICATIONS.
THE KEY TO SUCCESSFUL FIRING BEYOND THE DESIGN SPECIFICATIONS IS TO TEST FIRE. AS A GENERAL RULE OF THUMB, TEST FIRE BEYOND YOUR APPLICATION AND THEN “BACK OFF” OR REDUCE THE NUMBER OF SQUIBS BY AT LEAST 2 PER SERIES.
The user may find that the Phase III conservative design Firing specification Limits can be expanded. This is acceptable for Fireworks squib applications, whereas it would be an unacceptable practice in Commercial Blasting where an unfired shot poses an extreme Safety Hazard.
In all applications and testing the DAVEY FIRE SQUIB has been used. THE DAVEY FIRE SQUIB SEEMS TO BE SOMEWHAT MORE SENSITIVE, IN TERMS OF ELECTRICAL POWER REQUIRED TO FIRE, THAN OTHER SQUIBS, although very little testing has been done with squibs other than the Davey Fire.
1) Single Series – 1,250’ SHP (16ga Heavy Wire) Interconnecting Cable with 8 (eight) Davey Bickford Squibs and aprox. 600 feet of 22 ga. extension wire in series – SUCCESSFUL FIRE 8 SQUIBS. (aprox. 32.8 ohms total resistance; 8 x 1.9 ohms = 15.2 ohms squibs + 600’ x 16.14 ohms/1000’ = 9.7 ohms extension wire + 1,250’ x 3.15 ohms/500’ = 7.9 ohms Interconnecting Cable) = 240% beyond Single Series Rmax of 13.7 ohms – with load equivalent to 34.7 ohms (253% overload) No Fire.
2) (See Manual Section SAME ADDRESS FIRING ON DIFFERENT FIRING MODULES – MULTIPLE SHOTS); Multiple same address Firing Modules (FM); 3 Parallel Series – 1 FM w/ 725’ HP Interconnecting Cable and 6 Davey Bickford in series (22.6 ohms calc) + 1 FM w/ 425’ HP Interconnecting Cable and 8 Davey Bickford in series (21.7 ohms
Time code input to the modem section always originates at the master tape machine (via the play RCA phono jack, or in the case of the Field Controller to either the RCA jack or the 600 ohm balanced XLR male pin input jack). The master tape machine plays the music and time code on separate tracks of the tape. The music is routed to the P. A. System, Radio Broadcast, or both. The time code is routed to the play input of the System Controller.
When Firing in the field there are many options for getting the time code audio signal to the System Controller and the Music audio signal to the broadcast point (either P. A. or Radio or both). One way is to have the master tape machine at the firing location. The time code audio may thus be directly connected to the System Controller. The Music audio must then be sent to the broadcast location. This may be over equalized phone lines, special radio, or direct cable. Direct cable lines should be converted to a 600 ohm +4dbv balanced line by a line driver from the high impedance outputs of the tape machine to avoid high frequency audio losses.
If the master tape is played at a radio station then the time code must get reliably from the station to the firing site. This can be a voice grade phone line, special radios, or direct cable. The main disadvantage of having the radio play the tape is that you loose control. You no longer can stop or delay the time the music is played due to Safety or other considerations of which the radio stations may be unaware. IF THE RADIO STATION PLAYS THE TAPE THEN YOU SHOULD DEFINITELY HAVE A DIRECT VOICE LINK TO THE BROADCAST ENGINEER TO GIVE FINAL OK AND INSTRUCTIONS. SO THAT YOU ARE IN CONTROL.
Another possibility is an intermediate broadcast point, or master control location from which the master tape is played. From this point the P. A. is driven and it then becomes the radio stations responsibility to get the music from there. The time code may be direct cabled several thousand feet, using high impedance to 600 ohm balanced line and then back to high impedance. The time code may also be special radio broadcast for long distances or remote/multiple firing locations.
These audio considerations are only mentioned briefly to remind the user of their necessity. Details can be worked out with the sponsor/radio station/etc.. Having a person competent and qualified in professional audio attending to these details can surely help the success of the project.
THE KEY POINT IS THAT THE AUDIO LINKS FOR BOTH THE TIME CODE AND THE MUSIC ARE CRITICAL AND MUST BE RELIABLE. Backups and redundancy should be well considered.
IT IS IMPERATIVE THAT THE TIME CODE LINK BE CHECKED FOR INTEGRITY AND VALID TIME CODE TRANSMISSION. This means that before the Display you must have the tape played at the Broadcast Location (or wherever the master tape machine is located) and Verify your reception of the Time Code at the System Controller. The Hardware setup should be exactly as used for the Display.
IT IS HIGHLY RECOMMENDED THAT YOU PERIODICALLY CHECK THE TIME CODE LINK, AT LEAST AS SOON AS THE SYSTEM IS SETUP AND THEN JUST PRIOR TO THE DISPLAY. This will give you time to repair the Link or use alternate Firing Procedures should the Link fail just before Showtime.
It will be helpful to understand the actual structure of the Pyrodigital Time Code in order to properly verify the integrity of the Time Code Data. Knowledge of the time code will also assist the user in determining it’s transmission characteristics over phone lines, etc..
The Pyrodigital Time Code is like a mini version of SMPTE (Society of Motion Picture and Television Engineers) Time Code in that it is a “smart” Time Code. By being smart, we mean that each time number is a unique piece of data and the actual time can be determined from any one block of data. Some other non smart Time Codes are simple “pulses” and require resetting to the beginning of the time code stripe on the tape, each time, in order to count from the start. The Pyrodigital Time Code can be started from any point with full recovery of the actual time after only 1 valid frame of time code data.
The time code is actually an off BELL 202 Modem standard, 1200 baud, half duplex, FSK modem signal. Half duplex means that signal is only in one direction and FSK, or frequency shift keying is the type of modulation. This standard was developed, and is suitable for transmission over normal voice grade phone lines, however if transmitting over phone lines precautions must be taken to insure the integrity and quality of the phone line. A dedicated normal voice grade line, with a backup, is recommended at minimum. Full testing of the line using verifying procedures several times is absolutely required.
The time code itself consists of a distinct and unique number every 1/10 of a second. The time code is generated in a sequentially increasing manner, starting from zero to a maximum of 32,768 tenths of a second (16 to the 4th power divided by 2), in 1/10 second increments.
Each time code number starts with an S followed by 6 hex characters, the first 4 of which are the time code number and the last two characters is a truncated check sum. The zero time code is thus S000000, the next is S000101, 33 tenths is S002121. A hex to decimal conversion of the first four hex numbers will give the time in base ten tenths.
It is not important that you actually understand the actual time code structure, but that you understand that the time code must meet certain criteria to be valid. It must be sequential, it must be preceded by an S, and it must have the proper check sum. Any errors in the exact time code will be reported by the verifying procedures.
Some errors may or may not be acceptable. Due to the nature of the Auto Fire Mode (or Smart Fire) if 1 or 2 time codes are lost, the Firing will continue uninterrupted. When the valid time code is re-established, time will be updated to the incoming time code numbers (the Auto Time Switchover Feature). Certainly your time code on the master tape should be error free.
*****Insert Drawings Possible System Layouts here
The System Layout is comprised of two distinct areas, the Firing Area and the Control Location. The System Controller is at the Control Location which is separated by some distance from the Firing Area. The Firing Area contains the mortars and Pyrotechnic Devices as well as the Phase III System Network.
The link between the Firing Area and the System Controller is the main Interconnecting Cable. This Cable may be physically identical in every respect to the other Interconnecting Cables and thereby completely interchangeable. It is simply called the main Cable or trunk line. This main Cable may also be a heavier gauge Cable in order to minimize the power loss when traversing a long distance between the System Controller and the Firing Area.
The main Cable physically connects between the System Controller (which can be the Interface Box or Pyrodigital’s Computer) and the input on the first Splitter Box. This first Splitter Box may or may not be the only Splitter in the Network. If it is the only Splitter Box then it’s number of outputs will determine the maximum number of Firing Modules which may be connected to the System (or Network). Interconnecting Cables would leave the outputs from this single Splitter Box and connect to the Firing Modules. These Interconnecting Cables may be of varying lengths to accommodated the placement of the Firing Modules and still return to the common Splitter.
More than 1 Splitter Box may be used for 2 different reasons. One obvious reason is so that additional Firing Modules may be connected beyond the output capacity of the first or primary Splitter. The second reason is that it may be desirable or necessary to spread out the mortar set up or show layout.
The Splitter Box is like a grouping module. It connects various Interconnecting cables, and thus Firing Modules, to one common point. Several of these groups of Firing Modules may be further grouped by bringing in each common point, via additional Interconnecting Cables, to the primary Splitter. This then collects all the Firing Modules into 1 input which connects to the main Interconnecting Cable. (and to the System Controller)
All this grouping, or the reverse of Splitting, can be random and need follow any set pattern. There is no limit to the number of Splitter Boxes, hence Splits that may be used. The limit comes from the amount of Interconnecting Cable which may be used (power loss) and the number of Firing Modules which may be connected, 128 max. It is recommended, however, that the Splitting Sequence follow some logical order. The order should go from primary splits to secondary splits and then so on, before connecting to the Firing Modules. It is possible to connect to both some Firing Modules and additional Splitters from the primary split and then on to additional Splitters and then repeat a similar sequence on the secondary splits, and so on. This method, in fact, would be the most advantageous in economical use of Interconnecting Cables for a large linear and spread out set up.
Generally the setup would proceed in the reverse order, that is from the Firing Modules back through Interconnecting Cables and Splitters back via the main trunk line to the System Controller. THE FIRING MODULES AND THE ENTIRE SYSTEM SHOULD BE LAID OUT BEFORE AND CHECKED OUT BEFORE ANY PYROTECHNIC DEVICES ARE PRESENT AT THE FIRING AREA. This is normal procedure and generally the shooting setup would be laid out first, having mortars placed and dug in, or sanded, or nailed and secured racks, or whatever.
The Firing Modules are placed where they are needed. They are placed close to the mortars or Pyrotechnic Devices to be fired, so that the squib legwires may be connected easily and Safely without requiring scab (extension) wiring. (which eats up precious time) The Firing Modules may be placed on the sides of shoot boxes (if used), on the ground, or attached to the sides of racks. Holes are provided in the Firing Modules for temporary mounting purposes. Again the primary concern is to be able to connect all the squib wires without the use of scab wires, to save time. The Firing Module location should also permit the Shunt Operator to be able to have easy and Safe access and visibility to the Shunt Switch.
*****WARNING – EXTREME DANGER
THE FIRING MODULES, ALL ELECTRICAL CONNECTIONS, AND THE SYSTEM CONTROLLER MUST BE PROTECTED FROM THE RAIN OR WET ENVIRONMENTS. IF THE FIRING MODULE IS SUBMERSED OR DRENCHED IN WATER THE INTERNAL ELECTRONICS MAY FUNCTION IN AN ERRATIC AND UNPREDICTABLE MANNER AND PYROTECHNIC DEVICES MAY BE FIRED UPON A STATUS CHECK, OR AT ANY TIME.
IF THE FIRING MODULES, ALL ELECTRICAL CONNECTIONS, AND THE SYSTEM CONTROLLER ARE KEPT AS DRY AS THE PYROTECHNIC DEVICES WHICH YOU ARE ATTEMPTING TO IGNITE, THEN YOU SHOULD HAVE NO PROBLEMS.
KEEP ALL ELECTRICAL CONNECTIONS DRY, SUCH AS THE SPLITTER BOXES AND THE INTERCONNECTING CABLE ENDS. ELEVATE THE FIRING MODULES AND SPLITTER BOXES OFF THE GROUND TO KEEP THEM OUT OF POSSIBLE POOLS OF WATER. COVER AND PROTECT ALL ELECTRICAL CONNECTIONS FROM DIRECT RAINFALL.
OBVIOUSLY THE SYSTEM CONTROLLER SHOULD BE KEPT DRY, ESPECIALLY IF 110VAC IS PRESENT. AN ELECTROCUTION HAZARD IS ADDITIONALLY PRESENT WHEN MIXING WATER WITH 110VAC, AS WELL AS POSSIBLE ERRATIC AND UNPREDICTABLE FIRINGS.
PROPER PLACEMENT OF THE FIRING MODULES CANNOT BE OVER EMPHASIZED. Proper Placement will save time and simplify the squib connection procedure. These placement considerations should be considered well in advance of actually setting up the mortars, etc. Experience is the best guide, keeping in mind all Safety considerations with ease and simplicity of loading and electrical connection of the squibs.
If covering the Firing Modules and Splitter Boxes for protection against possible inclement weather, consider the possibility of the covering material becoming inflamed. Plastic Bags and/or Tarps can catch on Fire and will burn up any Firing Modules or other components that are covered by the Plastic bags and or Tarps. Plywood or Metal Covering offers better protection against catching Fire.
The Firing Modules should be positioned sideways, with respect to gravity. This is so that flaming debris will not come in permanent contact with the quick connector housing and damage the quick connectors. If bullwhip wires are present on the Firing Module then these wires should be routed so that they wont get burnt up on the ground or by falling debris.
Another very important consideration in FM (Firing Module) placement is the permanent connection of the squib wires. It is possible, especially when squibbing into the lift on an aerial shell or when stuffing excess wire into the mortar, for the squib wire to leave violently with the shell and pull loose or disconnect adjacent squib wires. The placement of the FM should be such that the squib legwires can be connected in an orderly and isolated fashion. This will prevent any one squib legwire from disconnecting any others. It may be also desirable to fix or attach the squib legwires is such a manner that the wire will break before if can become disconnected violently and thus disconnect adjacent wires.
Squib wire disconnection by previously fired shells is generally not a problem when squibbing to match leaders and the squibbed part of the leader hangs outside the mortar. The concern here becomes damage to the squib connectors by the burning match. This can be virtually eliminated by not placing the FM on the ground facing up directly underneath the shell leaders. (where the burning match can fall directly onto the squib quick connectors)
The Firing Module has provisions for connecting a squib to each of it’s 16 circuits. The type of squib connector is determined by type of Firing Module. Spring loaded quick connectors are the most common. Crocodile Clip connectors on a bullwhip, or group of wires may also be provided.
The connectors operation is obvious. This is the point at which you connect the squib (or squibs) and possibly any squib extension wire (scab wire) required for the Pyrotechnic Device to be fired. Most connectors are indicated Red for positive voltage and Black for ground. Each pair (red & black) corresponds to one of the 16 circuits so indicated in writing on the Firing Module or Crocodile Clip Boots. It does not matter which legwire of the squib is connected to hot (red) and which one is grounded (black). All the blacks are common ground. Be careful when inserting the wires in the squib quick connector so as to grab the wire, not the wire insulation.
It is possible to connect more than 1 squib on each circuit of each Firing Module. Refer to the Section; SQUIB FIRING POWER, MAXIMUM LIMITS; for limits and simple calculations to determine the maximum number of squibs which may be fired for your System and Layout. The maximum limits vary according to the size of your system, the squibs to be fired, and if any scab (squib extension) wire is used. Remember SERIES CONNECTION ONLY is recommended.
Once the Firing Modules have been placed the connection via the Interconnecting Cables and Splitter Boxes may proceed. The Splitter Box, which is to connect a series of FM, is placed at some distance away from the FM, and away from mortars and Pyrotechnic Devices. Interconnecting Cables, which may be of various lengths, are then connected from the Firing Modules to the Splitter Box. The Splitter Box position may be adjusted to provide maximum separation from the mortars within the lengths of Interconnecting Cable used. Shorter Cables may be used for closer Firing Modules. Experience will dictate a smooth, attractive, and efficient set up which is far more difficult to describe than to do, because of all the variations possible.
The Interconnecting Cables and Splitters thus allow all the Firing Modules to eventually brought back to one common point at the primary Splitter Box. One must be careful to be sure each and every Firing Module is connected by some path of Interconnecting Cables and Splitter Boxes back to the System Controller. A Splitter Box output connected back to it’s input will certainly leave some Firing Modules not connected to the Network. From the primary Splitter Box an Interconnecting Cable may then run to the System Controller.