Instruction manual

3. DESCRIPTION OF EACH MODULES
IMSRM15-E6
63
(3) Cascade control function
There are master control and slave control blocks for cascade control. The master control block
performs PID computation based on the temperature (measured value) at the measured point necessary
to be finally controlled and then corrects the set value of the slave control block using the cascade
signal. The slave control unit performs cascade temperature control by the set value corrected by the
cascade signal.
Cascade module function configuration diagram
PV1
SV1
PV2
SV2
PID control
SV monitor 1
Setting change rate limiter
Setting limiter
SV monitor 2
Cascade monitor Gain Bias
PV1
MV1
SV1
SV monitor 1
SV monitor 1- PV1
MV2
CH1
Master block
CH2
Slave block
For tracking on: If cascade control is turned off, the cascade
monitored value just before the control is
turned off is held as data.
For tracking off: If cascade control is turned off, the cascade
monitored value become 0.
If cascade control is turned off,
fixed to the captured
measured value just at the off
time
Cascade
ON
Slave output:
Heat/Cool control is
also available.
+
+
+
PID control
Setting change rate limiter
(4) Alarm function
One H-CIO module is provided with two alarm (Alarm 1 and Alarm 2) points as standard.
Alarm 1/2 types are those selected by the H-PCP module.
Alarm type:
Deviation high alarm Process high alarm
Deviation low alarm Process low alarm
Deviation high and low alarm Process high alarm with hold action
Band alarm Process low alarm with hold action
Deviation high alarm with hold action Deviation high alarm with re-hold action
Deviation low alarm with hold action Deviation low alarm with re-hold action
Deviation high and low alarm with hold action Deviation high and low alarm with re-hold action
Each alarm can be output as summary output (OR output) from the digital output block in the
H-PCP-A/B module. For details, refer to 3.3 H-PCP Module (P. 36).
The respective alarm (Alarm 1/2) can be output independently for each channel by
connecting the H-DO-A/B/D module. For details, refer to 3.9 H-DO Module (P. 70).