Celduc Temperature controller ECOM - Manuel (Page 50)

User manual - ECOM0010 51
The control output has to be configured as PID for Heating
(parameter 11
SE
greater than 0), while the alarm 1 has to be
configured as Cooling (write 7 in word 18
$/
). The control
output must be connected to the actuator making heating,
while the alarm will control cooling action.
Parameters to be configured for the heating PID are:
SE
(word 11): Heating proportional band
WL
(word 12): Integral time of heating and cooling
WG

XPSE


%FSJWBUJWF
UJNF
PG
IFBUJOH
BOE
DPPMJOH
WF
(word 14): Heating time cycle
Parameters to be configured for the cooling PID are:
$/
(word 18)= (value 7) Alarm 1 selection (Cooling)
SE0
(word 25): Proportional band multiplier
RXGE
(word 26): Overlapping / Dead band
FRFW
(word 27): Cooling cycle time
Parameter
SE0
(that ranges from 1.00 to 5.00) determines the
proportional band of cooling action basing on the formula:
Proportional band for cooling action =
SE
*
SE0
This gives a proportional band for cooling which will be the
same as heating band if
SE0
= 1.00, or 5 times greater if
SE0
= 5.00.
Integral and derivative time are the same for both actions.
The parameter
RXGE
determines the overlapping
percentage between the two actions. For systems in which
the heating output and cooling output must never be
simultaneously active a dead band (
RXGE
≤ 0) must be
configured, vice versa you can configure an overlapping
(
RXGE
> 0).
The following drawings show an example of dual PID action
(heating-cooling) with
WL
= 0 and
WG
= 0.