PA7300 Instruction Manual - TECO-Westinghouse Motor Company

(23) Frequency Command Upper-Bound Delay Time (Bn-23)The PA-PID option card application parameter. If the inverter output frequency afterPID controlling exceeds the frequency command upper bound (the Cn-14 set value),the relay output on PA-PID card will active to increase the pump numbers when thedelay time set by Bn-23 has expired.The set value of Bn-23 depends on the pressure response of water supply system,the set value is the smaller the better as long as the system pressure cannot vibrate.(24) Frequency Command Lower-Bound Delay Time (Bn-24)The PA-PID option card application parameter. If the inverter output frequency afterPID controlling drops below the frequency command lower bound (the Cn-15 setvalue), the relay output on PA-PID card will active to decrease the pump numberswhen the delay time set by Bn-24 has expired.The set value of Bn-24 depends on the pressure response of water supply system,the set value is as small as better if the system pressure cannot vibrate.Please refer to “PA-PID instruction manual”.(25) MC ON/OFF Delay Time (Bn-25)The PA-PID option card application parameter. Please refer to “PA-PID instructionmanual”.When switching one motor (or pump) driving by inverter to ac power source or viceversa set the MC ON/OFF delay time (set value of Bn-25) to avoid the inverter outputand ac power source being short-circuited due to the different operation delay time ofMC1 and MC2.The delay time (Bn-25 set value) must be longer than the time from the MC ON/OFFcontrolled signal output from inverter until the external MC operation.Generally, the MC operation time from OFF to ON is longer than ON to OFF, set thedelay time according to the longer one.AC power sourceInverterMC1MC2IM(26) Pump ON/OFF Detection Level (Bn-26)The PA-PID option card application parameter. Please refer to “PA-PID instructionmanual”.The set value of Bn-26 is the deviation level of PID aimed value and PID detectedvalue when using PA-PID option card to increase or reduce the pump numbers.Set the pump ON/OFF detection level in units of 0.1%. If the value is set to 0.0%,when output frequency reaches the frequency upper bound )the set value of Cn-14)increases the pump numbers immediately, and when output frequency drops to thefrequency lower bound (the set value of Cn-15) decreases the pump numbersimmediately.48