ABB ControlMaster Series Manual page 22

ControlMaster CM30
Universal process controller,
Auto / Manual station and analog backup station
These templates configure the CM30 to backup a master controller, typically a PLC or DCS. A fault condition is detected via a low
output signal from the master controller or a digital signal. On detection of a fault signal, the CM30 can take control of the
process (analog backup template), freeze its output or switch to a safe output (auto / manual station template). In this example, a
critical control of flow is backed-up by the CM30.
Flow
Fig. 23: Auto / Manual station and analog backup station
Dual loop
The dual loop template enables a CM30 to act as 2 independent controllers and is available with a remote setpoint for either, or
both, control loops. In this example, the temperature and humidity of a climatic chamber are controlled independently.
Fig. 24: Dual loop
14 DS/CM30–EN Rev. L | ControlMaster CM30 | Universal process controller,
/ DIN
1
4
PV
O/P
Master
Controller
FT
TT
HT
1 /
Master Control
Signal
O/P
PV
PV1
PV2
O/P2
O/P1
DIN
4