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Lithium Polymer (LiPO) Cell Chemistry Over-Discharge Protection Circuit Board

Price: 20.00 (USD)

The First Plug N Play Add on Board for the SW-COMPUTER Type MOSFET TRIGGERS Available at:

Also "Plug and Play" supported are the Unconvential-Airsoft.com Trigger Master Series of Computerized MOSFET Triggers.

Link to their product page.

PCB V4.X Assembly and Installation Part 1
PCB V4.X Assembly and Installation Part 2
Functional Demonstration Video

OPERATION MANUAL FOR PCB V4.X AVAILABLE HERE. (PDF)

ORDER FORM AVAILABLE HERE. (Save the PDF File to your computer, then you can fill out the interactive form, save the data, and email it to me.)

The image shown above is of a LiPO PCB V4.X I will send you connectors for your requested configuration.

See the bottom of this page for more pictures of everything you will get with your order.

Specifications:

Nominal Size = 1.18 x 0.675 x 0.145 inches (30 x 17 x 3.7 mm) (L x W x H)
Operating Range = 2, 3, and 4 Cell LiPO Packs (7.4, 11.1, 14.8 VDC Nominal Pack Voltages) (Packs fresh off of the charger can be higher voltage, the PCB will be fine.
Secondary Range = 2, 3, and 4 Cell LiFEPO4 Packs (Please email me for the special software change, pricing does not change for this configuration change.)
Operating Power Consumption = Less than 15 mA Idle (Pack OK) and Less than 30 mA when Indicating Weak or Dead cells
Trigger Mod Power Available = 25 mA for MOSFET Gate Pin (Firing) Signal
LEDs on the PCB for User Information = Green (Pack OK), Green + Yellow (Pack Weak), Red (Pack Dead). See the manual for more details.

Features:

1. Per Cell Voltage Monitoring, Ensures that no single cell will overdischarge below acceptable charging limits.
2. Design optimized for "Plug N Play" operation with Extreme-Fire.com SW-COMPUTER. (Requires software versions 2.7 or higher, contact myself or Gandolf if you need an upgrade or if you are unsure of your software version). If you bought your SW-COMPUTER or TRIGGER MASTER after March 2008, it is 2.7+.
3. Ultra low power consumption keeps power where you need it, on the motor.
4. User reconfigurable for different LiPO packs. Just plug in your other packs, no special jumpers or anything, just plug it in and watch it work!
5. Low profile design allows for placement in battery bay alongside monitored pack, can also fit in less space than your stock fuse holder space. Fits along side a MOSFET Trigger such as SW-COMPUTER with room to spare!
6. All wires, connectors, heat shrink, and even solder that are needed are supplied with your order.
7. Can be used in conjunction with MOSFET Trigger Circuits other than SW-COMPUTER via the Trigger Mod.

How It Works (With an SW-COMPUTER Type MOSFET Trigger):

1. The PCB constantly measures the voltage of each cell in your pack.
2. When the voltage of the pack spikes downward from firing, the PCB ignores these data values since they are lies. (The PCB only cares about steady state cell voltage which it calculates continuously.)
3. When any cell drops below a steady state of 3.2 volts (for a LiPO), the SW-COMPUTER is alerted of this via the SW-LINK Cable. The SW-COMPUTER will then indicate "Weak Battery".
4. The PCB continues to monitor the cells, looking for when any cell drops below a steady state of 3.0 volts (for a LiPO). The SW-COMPUTER is then alerted of a "Dead Battery" via the SW-LINK Cable.
5. Since the SW-COMPUTER is told the pack is dead, the AEG will not be allowed to fire and thus prohibits further discharging of the pack.

How It Works (With a MOSFET Trigger other than a SW-COMPUTER):

1. The PCB constantly measures the voltage of each cell in your pack.
2. When the voltage of the pack spikes downward from firing, the PCB ignores these data values for a short time. (The PCB only cares about steady state cell voltage.)
3. When any cell drops below a steady state of 3.2 volts (for a LiPO), the YELLOW LED on the PCB Board will turn on. (You will not see this since it is inside of the AEG)
4. The PCB continues to monitor the cells, looking for when any cell drops below a steady state of 3.0 volts (for a LiPO). The Trigger Mod Output then goes LOW (zero volts).
5. Since there is no power for your trigger and thus the MOSFET, the AEG will not be allowed to fire and thus prohibits further discharging of the pack

NOTE:
The TRIGGER MOD requires special (but very simple) wiring that is not shown on this page, consult the manual. The Trigger Mod is only required for MOSFETS that are NOT SW-COMPUTER TYPE MOSFET TRIGGERS. Trigger Mod must be noted on the order form as this is a hardware AND software modification to the PCB. Trigger Mod PCBs cannot be used with SW-COMPUTER Type MOSFETS and Standard PCBs cannot be used with non SW-COMPUTER Type MOSFETS due to these hardware and software changes. For more details, consult the manual.

Additional Notes:
1. The PCB requires at least a 2 Cell LiPO pack to function, 1 Cell simply doesn't have enough voltage to run the CPU (or fire your AEG nicely).
2. The PCB functions to prevent Over-Discharge NOT Over-Current draw, the SW-COMPUTER or a Fuse does this perfectly.
3. To prevent over-current draw (and the resulting thermal runaway which typically results in a fireball), use a LiPO Pack that is rated for 20 Amps or greater continuous discharge.
4. If using a LiPO Pack with any MOSFET Trigger OTHER than a SW-COMPUTER, use a 20A inline fuse to guarantee Over-Current Discharge Protection.
5. If at any time the AEG jams, DO NOT continue to attempt to fire the AEG, this will only cook the FETs, blow fuses, and/or risk damaging the LiPO Pack.
6. Do not leave the PCB connected to your battery pack when not in use, the PCB constantly draws a small amount of current and can over-discharge your pack if left connected for a long enough period of time.

Not intended for use with conventional (NiCD/NiMH/SLA) cell chemistry packs, failure to comply can damage the PCB and VOID ALL WARRANTIES.

If your LiPO Pack does not have balancing taps and you want to use a PCB, contact me and I will see what I can do about adding a balancing tap to your pack.

Quick Start Guide (Refer to the Manual for details, there are more things going on than I list here):

1. Connect the PCB to the SW-COMPUTER as shown: (This connection may be made indefinitely if you wish to leave the PCB in your AEG when not in use.)

2. Connect the Balancing Port to the PCB, the PCB will flash some startup codes, see the manual for details.
3. Connect the Main Power for the AEG and SW-COMPUTER, and the SW-COMPUTER self configures to use the PCB automatically.

After the SW-COMPUTER finishes initializing, the vibration indicating ready to fire will be long, rather than the default short vibration.
: Connect Balancing Tap - Connect Main Power - Short Vib. - Delay - Long Vib. - Ready to Fire

To Shutdown your AEG:

1. Disconnect the Main Power connection.
2. Disconnect the LiPO Power Tap connection used to monitor cell voltage. Do not leave PCB connected to your pack indefinitely!
3. Remove the battery pack from your AEG.

I accept payment via paypal. Send payment to sales@projectwolfdragon.com

Warranty Information

Questions? Please contact: sales@projectwolfdragon.com

Special Notes:
This product assumes that the buyer is able to disassemble and reassemble the AEG and/or mechbox fairly easily.
Rewiring and soldering will be needed for installation of this product.

If needed, please contact me to arrange for custom work.


 
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