Watlow 12LS Controller - Manual (Page 19)

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4. Use Thermocouple Extension Wire for all thermocouple (T/C) inputs. Most T/C Ext. Wire is solid wire
unshielded. When using such, the shield function cannot be utilized and only 16, 18, or 20 ga should be
used. Install all T/C wiring in its own conduit away from AC Power and High Power wiring.
Depending on type and wire size up to 400-500 feet in length may be used to be within stated accuracy and
source impedance.
5. Use multiconductor stranded shielded cable for analog inputs.
Most inputs will use a shielded twisted pair, but some may require a 3 wire input. Run all analog input wiring in
its own conduit away from AC Power and High Power wiring. Wire sizes of 20, 22, or 24 ga. may be used.
6. Use multiconductor stranded shielded cable for analog outputs and PID digital outputs connected to panel
mount SSR's. The analog output will normally use a twisted pair while the digital outputs will be up to 9 or 20
conductors depending on wiring techniques. All cables will be shielded. The wiring size will normally be 24
ga. The maximum length for the digital outputs should not exceed 25 feet. The maximum length for the
analog outputs should not exceed 400 feet. All wiring must be in a separate conduit away from AC
Power and High Power wiring.
When using the 50 conductor flat ribbon cable for the I/O, use of the 50-pin connector is recommended for both ends
of the cable. The wire is too small to withstand much flexing when connected to a screw terminal. The cable
length should not exceed 15 feet.
7. When installing communications wiring, by pulling in an extra pair, a sound power phone system could be utilized
for communications between the ANAFAZE controllers and the computer. This could be used for
maintenance, checking calibration and many other functions. A David Clark #H5030 sound powered system
has been used successfully in systems requiring this function.
8. When installing any I/O wiring to the ANAFAZE controllers inside a panel, it should never be run in the
same bundle as AC power wiring.
Also wiring bundles of low power ANAFAZE circuits next to bundles of high power AC wiring should never
be done. The physical separation of the high power circuits from the ANAFAZE controllers should be of
prime importance. In fact most AC voltage high power circuits are installed in a separate panel.