UNITED PROCESS CONTROLS GMBH
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Protherm 50 P68.230
Limits
PT50 makes four all-purpose limit values available, which can be used as single sided or double sided
limit comparator. The monitored value can be selected from a list of variables, which includes all im-
portant values. The switching threshold can be a fixed value or another value out of the list. With double
sided comparator a tolerance band is possible. The deviation alarm can be delayed and activate a relay
or assigned to a warning or alarm message.
The regulators in the PT50 features also independent relative and absolute limit values.
Warning - and alarm-system
Definition: A warning is a message, which will be automatically deleted after the disappearance of the
cause. Alarms has to be acknowledged by the operator or a process leading system.
Many functions of the PT50 generate limit - or status-messages, which informs the user. In accordance
with the meaning of the individual message, this must either only be taken to the knowledge with further
observation, or an immediate intervention is necessary. Since the situation is different in each case, a
solution was developed where an allocation of every limit or status message to a summary warning or a
summery alarm. A relay can be assigned individually to most of the messages.
A process leading system can read all limit - and status-data in two status-words, independent of their
functionality.
In the following description, functions which generates messages which allocation possibility to warn-
ings or alarms are marked with WA.
Allocation of system resources
Because of the many capabilities of the PT50, a fixed allocation of analogue and digital inputs/outputs
would waste resources. Therefore, these can be assigned to the functions with PT50 individually.
The allocation happens with the configuration of the functions, multiple-allocations are allowed only with
digital inputs.
The resources of the device can be expanded by CANopen – compatible I/O - modules. The corre-
sponding input/outputs are treated like internal resources and appear to the allocation-tables.
Names
Relay
-----
No relay assigned
IntRL1
Internally in the PT50 available relays
IntRL2
IntRL3
IntRL4
IntRL5
Gr1RL1
External relays group 1
The allocation depends on the CAN-Bus relay-module
Gr1RL2
Gr1RL3
Gr1RL4
Gr1RL5
Gr1RL6
Gr1RL7
Gr1RL8
