Pixsys ATR 142 User Manual

22 - ATR142 - User manual
8.12 Dual action heating-cooling
ATR142 is suitable also for systems requiring a combined
heating-cooling action.
Main command output must be configured foe hearting PID
(
act.t.
=
Heat
and
p. b .
must be greater than 0), and one of the
alarms (
A L .1
or
AL. 2
) must be configured as
co o L.
Command
output must be connected to the actuator responsible for
heat, while the alarm output will control cooling action.
Parameters to configure for the Heating PID are:
act.t.
=
Heat
Command output type (Heating)
p. b.
: Heating proportional band
t.i .
: Integral time of heating and cooling
t.d.
: Derivative time of heating and cooling
t. c.
: Heating time cycle
The parameters to configure for the Cooling PID are the
following (example: action associated to alarm1):
AL.1
=
cooL
Alarm1 selection (cooling)
p.b.m.
: Proportional band multiplier
ou.d.b.
: Overlapping/Dead band
co.t.c.
: Cooling time cycle
Parameter
p.b.m.
(that ranges from 1.00 to 5.00) determines
the proportional band of cooling basing on the formula:
Cooling proportional band =
p. b.
*
p.b.m.
This gives a proportional band for cooling which will be the
same as heating band if
p.b.m.
= 1.00, or 5 times greater if
p.b.m.
= 5.00. The integral time and derivative time are the
same for both actions.
Parameter
ou.d.b.
determines the overlapping percentage
between the two actions. For systems in which the heating
and cooling output must never be simultaneously active a
dead band (
ou.d.b.
≤ 0) can be configured, and viceversa an
overlapping (
ou.d.b.
> 0).
The following diagram shows an example of dual PID action
(heating-cooling) with
t.i .
= 0 and
t.d.
= 0.

Pixsys ATR 142 Specifications

General

Brand	Pixsys
Model	ATR 142
Category	Controller
Language	English