Description
If the level electrode (high or low level limiter) is installed inan isolatable level pot outside the boiler, make sure that thelevel pot is drained and the connecting lines are rinsed atregular intervals.For this purpose the connecting lines must be shut off andopened at regular intervals and by opening and closing thedrain valve the lines and the level pot will be rinsed.The logic unit SRL 6-40 is designed to be used in conjunctionwith control unit NRS 1-40.1 and NRS 1-40.2 to monitor thecorrect timing and sequence of valve operations.The equipment consists of a touch screen with integral PLCand I/O system. Its design is in accordance with EN 50156and the data exchange is effected via CAN bus using theCANopen protocol.
Function
The logic unit monitors the following times and processsequences:? Interval time: This is the time interval at which, depending on the operating mode (24h / 72h operation), theconnecting lines have to be purged.? Standby time: The purging process must be initiatedduring this time. The standby period begins when theinterval time has elapsed.? Purging time: During this period the valves must be operated so as to initiate the purging process. Operation of thevalves and exposure of the LW level electrode is sensedand signalled by the limit switches. If a message is notreceived during the purging time, the safety circuit willbe interrupted. The monitoring of the purging time is asafety-relevant function because a water level limiter maybe bypassed for a maximum of 5 minutes.
Datasheet(s) [PDF]
- gestra-srl6-40-14754.pdf
