Can anyone provide an example of a 3-pump Lead, Lag, and Standby control sequence? please
Can you give some more context? Are you doing the logic in Niagara (using NDIO/NRIO/IO-R for I/O)? Are you trying to balance runtime? Any scenario where you’d need more than one pump running? Constant speed or controlling to pressure?
thanks for your reply
The system consists of three pumps operating in a Lead/Lag/Standby configuration. The Lead pump shall rotate weekly to balance runtime. Under normal conditions, only the Lead pump shall operate. If the Lead pump speed exceeds 80% for more than 2 minutes, the Lag pump shall be enabled. The remaining pump shall remain in standby and automatically replace any failed operating pump.
pump speed depends on Differential pressure.
Using Niagara DIO’s
Do you have access to the vykonPro modules? They’ve got a RotationalLoadSequencer block that can handle the rotation. From there you could look at adding something simple like a greater than block set to 80% with a boolean delay that fires a NumericSwitch that tells the Sequencer that 2 loads are required. Simpler than a custom program and fairly flexible
Thanks and will follow the same