Carel srl: pCO Stage Controller
page 16
In case of connection to a serial printer this parameter must be 1, otherwise it is not possible to have access to the
printer branch.
P43 - identification number
The parameter allows the setting of the unit identification number (useful only in case of connection to a system of
supervision and/or remote assistance).
P44 - alarms with automatic or manual reset
P44=0
⇒
automatic. In the event that one or more alarm conditions are detected, pCO acts as following:
-
red LED behind key “alarm” lit;
-
buzzer activated;
-
alarm relay (changed over relay, normally energized) opens
Pressing key “alarm” silences the internal buzzer and pCO displays the list of alarm codes.
If the causes of the alarm
are no longer actived, every locked out device starts normal functioning and pCO acts as following:
-
alarm relay closes (from NO a NC);
-
the buzzer, if it has not been silenced yet by pressing key “alarm”, is de-activated;
-
red LED behind key “alarm” blinks.
If in this stage new alarms come up, pCO re-acts the inital procedure. The red LED, while blinking, informs the user
that alarm situations have been detected and that, now, they are no longer actived.
The codes of such alarms are memorized so the user is able to see these situations by means of key “alarm”; if,
after visualizing them, the user presses again key “alarm” they are definitely cancelled and red LED is de-activated.
P44=1
⇒
manual. In the event that one or more alarm conditions are detected, pCO acts as following:
-
red LED behind key “alarm” lit;
-
buzzer activated;
-
alarm relay NC contact (change over relay, normally energized) opens
Pressing key “alarm” silences the internal buzzer and pCO displays the list of alarm codes. If the alarm conditions
are no longer actived, the red LED blinks to inform that alarms has been detected but now they are no longer “true”.
In this situation alarm relay keeps the contact open to signal what happened. If now new alarms come up, pCO re-
acts the initial procedure.
Devices are locked out until the user cancels alarm messages from memory:
This is achieved by pressing key “alarm” while alarm codes are visualized in the display. If the reasons of the alarms
situations are effectively gone, pCO acts as following:
-
alarm relay closes NC contact (from NO a NC);
-
the buzzer, if it has not been silenced yet by pressing key “alarm”, is de-activated;
-
red LED behind key “alarm” is turned off.
Otherwise, if the alarm conditions are still actived, pCO re-acts the initial procedure.
P45 - delay on energizing alarm relay
The parameter allows the user to set a delay (minutes) between the detection of an alarm and the activation of the
alarm relay (digital output no.11). If P45 is zeroed, alarm relay acts immediately.
P46 - disabling key “On-Off”
The parameter disables the functioning of key “On-Off” to turn the unit off. If P46 is zeroed, the user is able to turn
the unit On and Off by means of the relative key, otherwise if P46 is equal to 1, key “on-off” allows only to turn the
unit on (it never stops).
P47 - serial communication baud-rate
This parameter permits to select the serial communication baud-rate. When the RS485 serial board is connected it is
possible to choose the data transmission speed :
0
1200 baud
1
2400 baud
2
4800 baud
3
9600 baud
4
19200 baud.
P61 - circuit 1 devices switch off mode
If P61=1, during the switch-off phase of the devices belonging to the circuit 1, first all the capacity-controllers and
then the respective compressors are switched off. This procedure is useful when a reduction of the number of
compressor switch on/off is required so as to protect their lifetime.
If P61=0, during the switch off phase current consumption is chosen.
example :
If in the unit there are
3 compressors (P4)
2 compressor capacity controllers (P6)
P61= 1
are selected and furthermore all the devices are switched on, when the switch off of the devices is
needed, first all the capacity controllers and only afterwards the compressors will be switched off.
Therefore, the situation could occur in which 3 compressors are switched on at the 33% of their
capacity.
step
claim
device
total number of devices switched on