Winco DPG-2145-001 - Manual (Page 7)

Manual 36526F DPG-21XX-00X Digital Controllers
Woodward v
EMC Limitations
Cabling
All cabling for this unit is limited to less than 30m (98.4’). See wiring diagrams for
specific cable types required.
Power cabling is limited to less than 10m (32.8’) in total length from its source;
power is intended to be from a local bus structure. The control is NOT intended
to have a power bus that is derived from a plant-wide distribution system, remote
source, or similar ―mains‖ type distribution systems. The power to the control
should also be a dedicated circuit, directly to the battery or source via a power
and return wire that are routed together.
See User Manual 36526 for additional regulatory information, limitations, and
wiring diagrams with specific, required cable types.
Power Bus
The power bus is intended to be a local bus without power line surges and to
have inductive load kickback events suppressed. Therefore, the control’s power
input is not designed to withstand a charging system load dump, heavy inductive
kickbacks, or heavy surge type pulses. If the control is installed outside its
intended usage, as described in this manual, centralized voltage pulse
suppression should be implemented to help protect the control and other
components on the bus. (See Chapter 6: Installation Instructions.)
COMM Port
The COMM port is intended to be a service port, with only temporary connection
during service or initial configuration. The COMM port is susceptible to some
EMC phenomena and possible unintentional battery return currents.
1. Battery return (B-) is also the communication signal common; typically
PCs conne ct the communication signal’s common to protective earth.
The PC grounding can provide an unintended return path for B- currents.
If B- and the PC are grounded to protective earth, a communication
isolator should be used between the PC and the control. Damage to the
PC or control, and/or unintended operation may result from a broken
battery return wire or the parallel path.
2. The pins inside the COMM port plug are susceptible to damage by ESD
discharges, static electricity arcs. Care should be taken not to touch
them with tools or put fingers into the port. Always touch your hand or
tool to a grounded piece of metal (discharge ESD) prior to coming in
contact with the communication port.
3. The input is susceptible to RF noise such as switching transients and
transmitter signals coupled into the communication cable. Cable
orientation and short cable length may be used to eliminate these issues,
depending on the severity of the environment.