ITT PumpSmart PS220, Руководство по конфигурации и эксплуатации

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PS220 Configuration & Operation Guide
PS220 162
Functions &
Features
Staging Pumps
Basic Theory of Staging.
The PS220 PumpSmart Multipump staging logic works based on 4 criteria:
1. A Pump is available with a Start Command Issued
2. The Process’s differential value between the setpoint and actual value.
3. Pump Speed
4. Stage Proof Time.
Once the Master Pump is running, the Multipump Control will stage the first Follower pump when:
1. The system differential value drops to the value of “Value Decrease”.
2. The Master pumps running speed reaches its” Stage Speed”.
3. The “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 during the proof time the proof time resets and start again until all 3 are again true.
The next available Follower in sequence with a start command will then stage on. The follower PS220 will ramp up,
with the Master controlling both, then will synchronize so that both will be running at identical speeds. Any remain-
ing pumps in the system that are available and have Start Commands will behave in the same fashion as the system
demand continues to increase. The Value configured for Max Pumps will determine how many lag pumps can stage in
the system when required.
The PS220 that receives the start command first in this ring format will automatically become the master.
Notes:
1. Staging values for up to 6 pumps are set to default values in the PS220 Multipump Functionality. For both Speed
and Torque, they are set to 98% of Max Speed, Parameter 30.12.
2. If you are using Torque/Smart Control in lieu of Speed (Parameter 81.04) All of the stage values need to be adjusted
to no more than 65%.
3. If you are using Process Variable you should “draw out”, and well define these stage values for all pumps. The de-
fault values WILL NOT WORK PROPERRLY
4. If any Follower/Lag faults off, that pump will immediately stop, and the system will start the next available lag.
5. If the Master/Lead faults the Master will be transferred to the running first running lag and will synchronize the
system.
Stage Proof Time
There is a default value set in the PS220 Multipump Functionality for “Stage Proof Time”. It is 20 Seconds.
Note:
For High Pressure controlled system it is recommend shortening this to no more than 3-5 seconds. A significant drop in
pressure may occur when the second pump stages as the system balances.