EVCO EPU2BXP1S1 - Manual (Page 54)

EVCO S.p.A. c-pro 3 micro SAVE/ c-pro 3 kilo SAVE | Application Manual ver. 1.0 | Code 144CP3UKSAE104
EVCO
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In case the control probe has an alarm condition it is possible to decide the number of heaters to be activated during
the the alarm by setting the Pb06 parameter. If Pb06=0 in probe error condition no heater is active.
Heaters thermal overload alarm
Via the DI6 (Electric heaters thermal overload protection) digital input it is possible to activate the heaters thermal
overload alarm. On occurrence of this alarm the heaters are immediately switched OFF. The alarm is signalled after a
fixed delay of 2 seconds and is reset automatically. The alarm is enabled by setting PA12=1. The alarm can be enabled
only if the heaters are configured (PG02=2, PG02=3).
6.8.5.4 Heaters status
Each of the three heaters can assume one out the following status:
1. Disabled: the heater is not managed by control.
2. Off: the heater is not active.
3. In switch-ON stand-by: the heater is about to switch-ON, it is in stand-by due to protection times.
4. In switch-OFF stand-by: the heater is about to switch-off, it is in stand-by due to protection times.
5. On: the heater is active.
6. Alarm: the heater is blocked due to the relevant thermal overload alarm.
7.
6.8.5.5 Heaters over temperature protection with
automatic reset
By setting the parameter PA16=1(high temperature) it is possible to decide whether to use the supply high
temperature alarms or not. The following parameters must be configured in order to use these alarms:
- PA17 = Automatic reset over temperature protection Set Point
- PA19 = Temperature alarm differential
- PA20 = Temperature alarm activation delay
The alarms are signalled after the PA20 delay time have automatic reset. The alarms are disabled in case of alarm
condition on the supply temperature probe. These alarms can only be activated with the unit running.
6.8.6 Heat exchanger by-pass in summer mode (Free-
Cooling)
During summer cycle, when the outside temperature is low enough it is possible to take advantage of the outside air
for cooling down the internal ambient by means of the by-pass damper. Set PG08=1 to enable this function. This
function uses the outside air temperature probe (TExt) and the return temperature probe (TInt).
When TExt ≥ Tke (default 15 °C, it can be modified by parameter Pr04) and return temperature TInt ≥ Tki (default 22
°C, it can be modified by parameter Pr05) and if TExt ≤ TInt the function is active and opens the heat exchanger by-
pass damper.
Note: To use this function the outside and return temperature probes must be enabled, respectively PH43=1 and
PH41=1. If one of the two probes is in error condition the function is disabled.