Hamilton Sundstrand Company Gas Fuel Metering Valve HFG2.0 - Manual (Page 29)

Recommended Wiring for System Signals
The recommended wiring is a 17-conductor shielded cable containing
twisted-pair wires with individual shields. Use a wire size large enough to
accommodate the installation and provide a maximum fifty (50) ohm loop
resistance. See Table 1-6 for recommended wire sizes.
DISTANCE TO USER’S
CONTROLLER
RECOMMENDED
WIRE SIZE
(Minimum)
≤ 1000 ft. AWG 18, stranded
> 1000 ft. Consult Factory
Table 1-6. Wire Size for HFG2.0 Signal Harness
Note: Use a separate conduit for the signal wiring. This prevents
noise pickup and transmission from ancillary equipment,
which could cause instability in the actuator. If conduit is not
used, signal wires should be at least 4-6 inches from any
other wires.
Ensure that all shielded cables are twisted conductor pairs with either a
foil or braided shield. PECC recommends Belden 8719 shielded twisted-
pair audio, broadcast and instrumentation cable. All signal lines should be
shielded to prevent picking up stray signals. Connect shields as shown in
Figure 1-12. Wire exposed beyond the shield should be as short as
possible.
CAUTION
This valve is 89/339/EEC EMC Directive compliant (CE mark) using
watertight, flexible conduit (plastic over steel) and Belden 8719
shielded, twisted pair-audio, broadcast and instrumentation cable.
Use of other conduit or wire invalidates EMC Directive compliance.
Do not connect 24 VDC power without current limiting (25 mA)
across digital or analog outputs.
INSTALLING THE HFG2.0 23