Interfaces and software update
Chapter 6
OPERATION MANUAL
V1.2.0en/12.05.15//14.06
Liability for errors and misprints excluded.
Unistat® T300 Series
73
Note that you may only change
>Com.G@te<
[46] when the temperature control unit is turned off.
In the category “Interfaces” you can change the settings of each function such as PoKo, analog
interface and RS232/RS485.
You may order
>Com.G@te<
[46] with Order No. 6915. You can extend an existing
>Com.G@te<
[46] via a connecting cable (Order No. 16160).
6.3.1
Jack LEVEL (Com.G@te® external only)
For level monitoring in the
>Sight glass<
[23].
This connection enables you to connect an external float switch (Order No. 6152), which is posi-
tioned in the
>Sight glass<
[23], for monitoring the level of your externally closed application. Acti-
vation via a potential-free contact.
The interface is specified as a digital input. Do not apply voltage or current.
Pin
Description
1
Level test (bypass via contact 2 → “absence”)
2
Level – (GND)
3
Level + (normally open contact)
6.3.2
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 circulation pump in the temperature control unit if an
external pressure booster pump is used in your temperature control circuit, i.e. the POKO as-
sumes the OK state as soon as the internal circulation is started up.
PCS: The POKO is used to communicate the state of the temperature control unit to the process
control system.
POKO condition
ON
means the pump is running.
POKO condition
OFF
means the pump is not running, the temperature control unit is in stand-by
mode.
▪
“Control via RS232”:
A special command on the serial interface is used to switch the POKO on and
off. Please also refer to the software offered by us.
Pin assignment
