Dual Action (Heating-Cooling) - Pixsys ATR244-12ABC Manual De Instalación

8.9

Dual Action (Heating-Cooling)

ATR244 is suitable also for systems requiring a combined heating-cooling action.
The command output has to be configured as PID for Heating (Par. 38
or greater than 0), and one of the alarms (
P.b. 1 P.b. 2
configured as
cooL.
The command output must be connected to the actuator responsible for heating, while the alarm will
control cooling action.
Parameters to be configured for the heating PID are:
or =
ac.t. 1 ac.t.2 Heat
or : Heating proportional band;
P.b. 1 p.b. 2
or : Integral time of heating and cooling;
i.t. 1 i.t. 2
or : Derivative time of heating and cooling;
d.t. 1 d.t. 2
or : Heating time cycle.
c.t. 1 c.t. 2
Parameters to be configured for the cooling PID related to regulation loop 1 and alarm 1 are:
= Alarm 1 selection (Cooling);
AL. 1 .F. cooL.
: Proportional band multiplier;
p.b.m. 1
: Overlapping / Dead band;
o.d.b. 1
: Cooling time cycle.
c.c.t. 1
Par. (that ranges from 1.00 to 5.00) determines the proportional band of
p.b.m. 1
cooling action basing on the formula:
Proportional band for cooling action =
This gives a proportional band for cooling which will be the same as heating band if
times greater if
p.b.m. 1
Integral and derivative time are the same for both actions.
Par. determines the percentage overlapping between the two actions. For systems in which
o.d.b. 1
the heating output and cooling output must never be simultaneously active a Dead Band (
must be configured, vice versa you can configure an overlapping (
The following figure shows an example of dual action PID (heating-cooling) with
SPV
SPV
PV
1
PV
ACTIVE
ACTIVE
ACTIVE
ACTIVE
SPV
2 SPV
PV
PV
ACTIVE
ACTIVE
ACTIVE
ACTIVE
Parameter has the same meaning of cycle time for heating action
c.c.T. 1
Parameter (Cooling Fluid) pre-selects the proportional band multiplier
co.f. 1
SPV
cycle time according to cooling fluid type:
c.c.T. 1
SPV
PV
co.f. 1
PV
Air
ACTIVE
ACTIVE
oiL
ACTIVE
H2o
ACTIVE
Once parameter
co.f. 1
modified.
Command output action type (Heating);
= 5.00.
 x  = COOL
 x  = COOL
 < 0
 < 0
 (HEAT)
 (HEAT)
COMMAND OUTPUT (HEAT)
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
ALARM OUTPUT (COOL)
 x  = COOL
 x  = COOL
 = 0
 = 0
 (HEAT)
 (HEAT)
COMMAND OUTPUT (HEAT)
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
ALARM OUTPUT (COOL)
 x  = COOL
 x  = COOL
 > 0
 > 0
 (HEAT)
Cooling fluid type
 (HEAT)
Air
COMMAND OUTPUT (HEAT)
Oil
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
Water
ALARM OUTPUT (COOL)
has been selected, the parameters
,
AL. 1 .F. AL.2.f.
SPV
PV
x
p.b. 1 p.b.m. 1 .
SPV
PV
SPV
3
PV
p.b.m. 1
or Par. 57
ac.t. 1
, , ,
AL.3.f. AL. 4 .f. AL.5.f.
ACTIVE
ACTIVE
ACTIVE
> 0).
o.d.b. 1
ACTIVE
ACTIVE
ACTIVE
c.t. 1.
p.b.m. 1
c.c.t. 1
1.00
1.25
2.50
, and
p.b.m. 1 o.d.b. 1 c.c.T. 1
= and
ac.t.2 Heat
or ) has to be
AL.5.F.
 x  = COOL
 < 0
 (HEAT)
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
= 1.00, or 5
 x  = COOL
p.b.m. 1
 = 0
 (HEAT)
≤ 0),
o.d.b. 1
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
= 0 e = 0.
i.t. 1 d.t. 1
 x  = COOL
 > 0
 (HEAT)
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
and the cooling PID
10
4
2
can be however
User manual - ATR244 - 21