
Manual 35086
ProTech-GII with Math Functions
Woodward
38
Shielded Wiring
All shielded cable must be twisted conductor pairs with either a foil or a braided shield. A braided shield is
preferred and highly recommended. All analog and communication signal lines should be shielded to
prevent picking up stray signals from adjacent equipment. Connect the shields as shown in the control
wiring diagram (Figure 2-7). Wire exposed beyond the shield must not exceed 50 mm (2 inches). The
shield termination should be done with the shield by opening the braid and pulling the wires through, not
with an added wire. If a wire is used it must be the largest gauge accepted by the shield lug terminal. The
other end of the shield must be left open or grounded through a capacitor and insulated from any other
conductor. Do not run shielded signal wires with other wires carrying large currents or high voltages. See
Woodward manual 50532,
EMI Control in Electronic Governing Systems
, for more information.
Installations with severe electromagnetic interference (EMI) may require relay and discrete input wiring to
be shielded, conduits and/or double shielded wire may be needed, or other precautions may have to be
taken. These additional precautions may be implemented in any installation. Contact Woodward for more
information.
Control Wiring Guidelines
Electrical Connections
EXPLOSION HAZARD—Do not connect or disconnect while circuit is
live unless area is known to be non-hazardous.
Plug-in screw-type terminal blocks are used to connect field wiring to each ProTech-GII module and to
the trip (interposing) relay contacts.
The size of the field wiring to the ProTech system should be between 1.5 and 6 mm² (16 and 10 AWG) for
power supply wiring and between 0.3 and 4 mm² (22 and 12 AWG) for all other I/O wiring. Wires for the
all the pluggable I/O terminal blocks should be stripped at 8 mm (0.3 inch). Torque and screwdriver
requirements are listed below.
The screw lug terminal blocks are designed to flatten stranded wire.
Do not tin (solder) the wire’s strands that terminate at the ProTech
Terminal Blocks. If the wire strands are soldered together, the solder
will cold flow and shrink over time causing the connection to become
intermittent or disconnected.
Woodward recommends the following for ProTech-GII:
Stranded bare copper wire (unless gaseous Sulfur
compounds are present) at the wire ends
Stranded copper wire with individually tin plated strands at
the wire ends
Hollow ferrules at the wire ends
Use single wire per terminal. There are enough terminals
provided for all I/O wiring
Released