Interfaces and software update
Chapter 6
OPERATION MANUAL
V2.3.0en/22.04.20//17.12
Heat Transfer Station eo
63
Pin
Signal
1
I+
2
U+
3
U−
4
I−
6.2.2
Interfaces at the back
6.2.2.1
Connector POKO (floating contact) alarm
Signal contact for external monitoring.
Notice the functions provided by PoKo in the category “Interfaces”. The potential-free contact
(PoKo) signals the state of the temperature control unit via the contact position. A closed operating
contact means readiness for operation. If a fault or an error occurs, the operating contact is opened
(this applies to the make contact between pin 1 and pin 2).
The following settings are offered:
▪
“Off”:
The POKO displays the OK state whenever the temperature control unit is ready for opera-
tion. The unit is ready for operation about 30 seconds after switching on, once the internal con-
troller check has been completed. The OK status is terminated by switching off the unit or in case
a fault occurs.
▪
“Internal temperature relative":
Set the upper and lower limit of a temperature range around
the setpoint by using the POKO “min. value” and the POKO “max. value”.
The potential-free contact indicates the condition, that the setpoint differs from the actual value
by a smaller difference than was defined by the temperature range. Exceeding the set range only
results in the potential-free contact to switch (away from the OK state), but does not result in fur-
ther reactions of the temperature control unit. The contact returns to the OK status if the actual
value is within that range.
▪
“External alarm”:
The POKO relay becomes active (OK state) in this function only, if the tempera-
ture control unit is switched on and is in “Fault” mode. The advantage is that the alarm will not be
triggered if the temperature control unit is switched off. Please use the POKO function
“OFF”
if
the alarm function is wanted together with the operating current principle.
▪
“Unipump/PCS”:
This POKO function and the enable contact of the pump guarantee that the
external pump runs synchronously with the pump in the temperature control unit if an external
Pin assignment
Standard interfaces at
the back
