# Interfaces & Wiring
## Safety Information
{% hint style="danger" %}
DO NOT CONNECT MODULE CELL INPUTS ACROSS MID-PACK SWITCHES, CONTACTORS OR SHUNTS
{% endhint %}
{% hint style="danger" %}
UNPLUG MODULE BATTERY CELL INTERFACES BEFORE BATTERY MAINTENANCE
{% endhint %}
{% hint style="danger" %}
VERIFY CELL VOLTAGES ON NEW INSTALLATIONS BEFORE CONNECTING TO MODULE
{% endhint %}
{% hint style="info" %}
All pinouts are looking into the module, "through" the wire housing.
{% endhint %}
## Isolation & Voltage Rating
The module is designed to provide a 1kV isolation barrier between the Battery Cell Interface J1 and the Power, CAN Interfaces J2/J3.
{% hint style="warning" %}
It is **not** recommended to connect GND to IGND, as this compromises the isolation barrier.
{% endhint %}
{% hint style="warning" %}
It is important to verify that other devices on the shared Power, CAN Interface are also isolated from the battery pack.
{% endhint %}
## J1 - Battery Cell Interface
### Wiring Considerations - Cell Taps
{% hint style="warning" %}
Correct wire selection is essential for mitigating the risk of cell tap shorts.
{% endhint %}
MPPE or PTFE insulated 24 to 20 AWG stranded wire is recommended. See [#tools-and-parts-battery-cell-interface](#tools-and-parts-battery-cell-interface "mention").
MPPE and PTFE provide good temperature and abrasion resistance.
Cell tap wires must be routed correctly to ensure they do not chafe or rub against any objects that could cause abrasion, and are not near hot surfaces or flammable materials.
It is recommended to keep cell tap wiring away from high current noisy conductors to minimise coupling and ensure good measurement accuracy.
### Temperature Sensors
Free hanging, insulated lead, two wire **10K 1% B25/85 3435K** NTCs are suitable, such as Vishay NTCLE and NTCA series.
{% hint style="info" %}
Ensure the correct crimps are used for the specific NTC's wire gauge.
{% endhint %}
### BMS106 Pinout
| Wurth Elektronik | 66200413722DEC |
| Wire Crimp Tool | Wurth Elektronik | 600001 |
| Wire Crimp Die | Wurth Elektronik | 600300300001 |
|
Wire
(or equivalent)
| Alpha Wire | 6713 OR |
## J2, J3 - Power, CAN Interface
{% hint style="info" %}
Power, CAN Interface pinouts are the same between all variants.
{% endhint %}
### Wiring Considerations - Power, CAN Interface
{% hint style="warning" %}
External devices connected to the module's Power, CAN Interface **must** share a common ground with the module.
{% endhint %}
Shielded, 4-wire, dual twisted pair, 20 to 24 AWG cable with 120 Ohm characteristic impedance is recommended. See [#tools-and-parts-power-can-interface](#tools-and-parts-power-can-interface "mention").
Shield termination and pass-through are available on the module, it is recommended to only terminate the shield to ground at a single point to avoid ground loops.
Due to the module's connector types an unshielded and untwisted section of the harness is inevitable. It is recommended to keep this section as short as possible.
Unshielded harnesses may work in certain low noise, short run installations, it is the integrator's responsibility to verify performance and integrity of the final wiring configuration.
BMS100 J2 & J3 Pinouts - Looking into module.
### Signal Descriptions - Power, CAN Interface
| Pin Name | Description | Notes |
| -------- | ----------------------------------- | --------------------------- |
| PWR |
Module Power
(IN/OUT)
| 6 - 36VDC |
| GND | Module Reference | Voltage bus return |
| CANH | CAN High | |
| CANL | CAN Low | |
| CANL\_T | CAN 120R Termination | Connect to CAN Low |
| SH | Shield Pass-through | Connected between J2/J3 |
| SHGND | Shield Termination | Internally connected to GND |
### Tools & Parts - Power, CAN Interface
| Tool/Part | Manufacturer | Manufacturer Part Number |
| ----------------------------------- | ---------------- | ------------------------ |
| Header | Wurth Elektronik | 66200621022 |
| Receptacle | Wurth Elektronik | 662006113322 |
| Wire Crimps | Wurth Elektronik | 66200113722DEC |
| Wire Crimp Tool | Wurth Elektronik | 600001 |
| Wire Crimp Die | Wurth Elektronik | 600300300001 |
|
Cable
(or equivalent)
| LAPP | 2170343 |
###
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