Watlow Series F4P - Manual (Page 71)

Wa t l o w S e r i e s F 4 P F e a t u r e s ■ 7 . 1 3
Duplex
Certain systems require that a single process output con-
trol both heating and cooling outputs. A Series F4P con-
troller with a process output in output 1A (F4P _ - F _ A
A - _ _ _ _) can function as two separate outputs.
With a 4 to 20mA output the heating output, for in-
stance, will operate from 12 to 20mA (0 to +100%) and
the cooling outputs will operate from 12 to 4mA (0 to -
100%). In some cases this type of output is required by
the device that the Series F4P controls, such as a three-
way valve that opens one way with a 12 to 20mA signal
and opens the other way with a 4 to 12mA signal. This
feature reduces the overall system cost by using a single
output to act as two outputs.
Location in software: Setup Page > Control Output 1A >
Function.
Figure 7.13 — Duplex Application Example.
input 1 output 1
hot water
cold water
temperature
transmitter
Fluid Sample Container
F 4
1
2
1B 1B
1A 1A
A M /
4 - 12 mA
-100 to 0% power
Cooling Off Heating
12 - 20 mA
0 to100% power
4 - 20 mA Output