ITT PumpSmart PS220, Руководство по конфигурации и эксплуатации

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PS220 Configuration & Operation Guide
163 PS220
Function & F
eatures
Staging Pumps
Basic Theory of Destaging.
The PS220 PumpSmart Multipump de-staging logic works based on 4 criteria:
1. Follower/Lag Pump is running
2. The Process’s differential value between the setpoint and actual value.
3. Pump Speeds
4. De-Stage Proof Time.
Once a Follower is running, the Multipump Control will de-stage the last Follower when:
1. The system differential increases to the value of Pressure Setpoint Actual.
2. The Master pump and any running Follower have reduced in speed to the “De-Stage Speed” (based on quantity of
pumps running, Destage 3, 2 etc.)
3. De-stage Proof Time has expired.
NOTE: All 3 of these have to be valid during the proof period. If either item 1, or item 2 changes to below the thresh-
olds noted during the proof time the proof time resets and starts again until all 3 are again true.
The last Follower in the sequence will then de-stage off. The follower PS220 will ramp down, with the Master con-
trolling both, then will synchronize so that both will be running at identical speeds. Any remaining pumps in the sys-
tem that have been stage on will behave in the same fashion as the system demand continues to decrease. The Value
configured for Max Pumps will determine how many lag pumps can de-stage in the system when required.
Pumps will de-stage in a 6-5-4-3-2-1 ring fashion unless a pump was offline and brought into the staging sequence
“Out of the ring order”.
There is a default value set in the PS220 Multipump Functionality for De-Stage Proof Time. It is 20 Seconds.
PAR 81.02
PAR 81.09
PAR 81.10 PAR 81.11