Wiring Guidelines - Best Practice For Grounding - Deif SGC 420 User Manual

Communication
Communication ports for CAN (terminals 58 and 59) and RS-485 (terminals 31 and 32) have built-in 120 Ω termination
resistors.
Digital outputs
If a digital output is connected to a relay, the relay must include freewheeling diodes.
2.5.2

Wiring guidelines - best practice for grounding

It is important to follow these wiring guidelines to get:
• Reliable readings from the sensors.
• Precise measurement of AC voltage and current.
• Best protection from lightning and other earth faults.
Example: Typical grounding setup
1. Terminal 16 (sensor common point) must be connected to a solidly grounded point on the engine, for example the
engine frame. The potential difference to terminal 1 (BAT-) must be less than ±0.5 V.
2. Do not connect the starter motor relay and the stop solenoid directly to the output terminals on the controller. You can
configure any of the outputs as run coil and crank.
3. Connect the shield to the engine ECU as described by the engine manufacturer.
4. Current transformers.
5. Power supply DC- (terminal 1) must be connected to BAT- (in this example, the engine).
6. Connect the digital inputs to ground to active the negative switching.
7. The 4th current is placed on line from the generator output PE.
8. Protected earth for the generator output.
User manual 4189341341B EN Page 13 of 89