Heater Break Alarm On Ct (Current Transformer); Dual Action (Heating-Cooling) - Wachendorff URDR001A User Manual

7.8

Heater Break Alarm on CT (Current Transformer)

This function allows to measure load current to manage an alarm during a malfunctioning with power
in short circuit, always open or partial break of the charge. To enable this function set
par. 287 and the value of the connected transfomer, on par. 288
ct F.
• Select on par. 290
• Select on par. 291
• Select on par. 292
• It is possible to associate an alarm, selecting
or par. 177 or par. 195
aL. 4 .F.
It is possible to visualize on display 2 the average current, selecting
Selecting 0 on par. 290
an Heater Break Alarm.
7.9

Dual Action (Heating-Cooling)

DRR244 is suitable also for systems requiring a combined heating-cooling action.
The command output has to be configured as PID for Heating (Par. 38
than 0), and one of the alarms (
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:
= Command output action type (Heating);
ac.t. 1 Heat
: Heating proportional band;
P.b. 1
: Integral time of heating and cooling;
i.t. 1
: Derivative time of heating and cooling;
d.t. 1
: Heating time cycle.
c.t. 1
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
1
PV
ACTIVE
15 - URDR001A - User manual
SPV
the Heater Break Alarm intervention threshold in Ampere.
H.b.a.t.
the intervention threshold in Ampere to control the overcurrent.
ocu.t.
the delay time in seconds for the Heater Break Alarm intervention.
H.b.a.d.
.
aL.5.F.
it is possible to visualize the current consumption without generating
H.b.A.t.
,
AL. 1 .F. AL.2.f.
= 5.00.
ACTIVE
on par. 123
H.b.a.
, , ,
AL.3.f. AL. 4 .f. AL.5.f.
x
p.b. 1 p.b.m. 1 .
 x  = COOL
 < 0
 (HEAT)
COMMAND OUTPUT (HEAT)
ALARM OUTPUT (COOL)
 x  = COOL
 = 0
.
ct v.
on par. 141
aL. 1 .F.
on par. 278
AMPEr.
=
ac.t. 1 Heat
) has to be configured as
> 0).
o.d.b. 1
or on
50 Hz 60 Hz
or par. 159
aL.2.F. aL.3.F.
.
vi.d.2
and greater
P.b. 1
cooL.
= 1.00, or 5
p.b.m. 1
≤ 0),
o.d.b. 1
= 0 e = 0.
i.t. 1 d.t. 1