Siemens HydroRanger 200 HMI, Руководство по эксплуатации

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Pump control reference
B.9 Service Ratio Duty Assist
HydroRanger 200 HMI
318
Operating Instructions, 06/2018, A5E36281317-AC
B.9 Service Ratio Duty Assist
Relay function (2.8.1.4.) (Page 195) =
Service Ratio Duty Assist selects the lead pump
based on number of hours each pump has run and the specified ratios that each pump
requires. Multiple pumps can run at one time.
Relay operation
(for Relay logic (2.8.1.11.) (Page 199) = Positive)
The setpoints associated with the relays are grouped so they can be redistributed based on
pump RUN time ratios. The next pump to start or stop is the one with the required time to
actual time ratio.
Over time, the number of hours demanded of each pump will conform to the ratios specified.
Usually, the ratios are specified in percent values.
To create a grouping of pumps where two pumps make up 50 % of the run time and the third
pump makes up the other 50 %, Service ratio (2.8.1.12.) (Page 200) is set to the following:
Relay Index Value
1 25
2 25
3 50
B.10 Service Ratio Duty Backup
Relay function (2.8.1.4.) (Page 195) =
Service Ratio Duty Backup selects the lead pump
based on the number of hours each pump has run and the specified ratios that each pump
requires. Only one pump can run at a time.
This algorithm is the same as Service Ratio Duty Assist except that it will run only one pump
at a time. When the next pump in the sequence starts, the previous pump stops.
B.11 First In First Out
Relay function (2.8.1.4.) (Page 195) =
First In First Out selects the lead pump based on the
Alternate
duty, but uses staggered OFF setpoints and shuts down pumps based on the first
in, first out
rule.
This algorithm starts pumps in the same way as Alternate Duty Assist but uses staggered
OFF setpoints to shut the pumps down. When the first OFF setpoint is reached, the FIFO
rule shuts down the first pump started. For example: pumps started in sequence 2, 3, 1
would be shut down in sequence 2, 3, 1.