GESTRA URS 60, Оригинальное руководство по установке и эксплуатации

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14 URS 60, URS 61 - Installation & Operating Manual -
819634-00
Function
The URS 60 / URS 61 safety control unit cyclically evaluates data telegrams from up to four safety sensors
of types NRG 1..., NRG 2…, LRG 1… and TRV 5. The data are transferred to an ISO 11898 CAN bus via
the CANopen protocol and saved. The safety functions are monitored by cyclical self-tests. The two inte-
grated relays are switched off in the event of alarms or failures. Function tests and failure diagnosis can
be conducted using either the control unit or the operating terminal.
The data telegrams contain the following information:
■ ■
Alarms from sensors if limit values are exceeded
■ ■
Error signals in the event of faults in electronic or mechanical parts
■ ■
Excessive temperature in the sensor terminal boxes
Behaviour on the occurrence of alarms
When level, temperature or conductivity alarms are received, both output contacts are opened after a
power-off delay, and this interrupts the safety circuit (fail-safe position). In this case, the safety control
unit does not lock independently; this function must be implemented in the downstream circuit. The URS
60 or URS 61 can only activate one safety circuit (heating or pump) at any one time.
The safety circuit is interrupted without delay if the following error messages are received:
■ ■
Fault in sensors (negative self-test, excessively high temperature in terminal box)
■ ■
Fault in control unit (negative self-test)
■ ■
Communication failure
Behaviour on the occurrence of error messages
Cyclical self-tests monitor the safety functions of the equipment in the safety control unit and sensors.
Error messages are updated with each self-test. If there are no faults, the malfunction indication is auto-
matically deleted and the output contacts are closed once more. Alarms and error messages are displayed
by LEDs or an operating unit.
In addition, you can choose to display alarms on an external signalling device via signalling outputs, either
with or without a delay. Faults are always indicated without a delay, however.
Alarm simulation
You can simulate alarms by pressing the button or via external 24 V DC signals.
Monitoring flushing processes
If a level electrode is installed in a lockable level pot outside the boiler, the connecting pipes must be
flushed regularly. During this flushing, no water level is measured in the level pot for up to five minutes.
Therefore, the URS 60 / URS 61 safety control unit bridges the level electrode as prompted by an SRL
6-60 monitoring logic unit, and monitors the maximum bridging time.
If the steam pipe is ≥ 40 mm and the water pipe is ≥ 100 mm, installation is regarded as internal. In this
case, upstream monitoring of flushing processes can be dispensed with.