Franklin Electric Cerus X-Drive, Инструкция по установке и эксплуатации

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ADVANCED APPLICATION OPTIONS
Multi-Motor Configurations
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Multi-Motor (MMC) Relay Control for Pump Applications
The multi-motor configuration for constant pressure systems provides control for up to 4 pump motors (8
with optional I/O board) in a Lead, Lag configuration.
The VFD controls speed of the Lead pump using its own PID feedback loop and the VFD motor output. If the
Lead pump cannot maintain setpoint pressure, the VFD uses relay outputs to trigger Lag pumps through a
starter, soft-starter, or another VFD. Relay output function
[IO–47, –48, or –49 etc.] should be set to 47_MMC Out .
The lowest number relay set to MMC will be Lag 1.
This feature does not provide an alternation or Lead pump replacement in case of pump or VFD failure.
To enable Lead, Lag Relay Control, set the following parameters:
MMC Mode [ADV–10]: Set to 3_Lead-Lag .
Lag Start Freq [ADV–18]: When the lead pump runs above this frequency, it sets the first condition for
starting a Lag pump. Range is Lag Stop Freq [ADV–23] to PID Hi Hz Limit [SET–23] . Default = 59.5 Hz.
Lag Start Delay [ADV–19]: Sets a delay time to start Lag pump when both frequency and pressure condi -
tions are met. Default = 10 sec.
Lag Start Level [ADV–20]: Sets a percentage below
PID F/B Max [SET–20]
(pressure) to calculate
MMC Below Set -
point as the second condition for starting a Lag pump. Range is 0.1 to 10%. Default = 2%.
MMC Below Setpoint
=
[SET–21] – {[SET–20] x [ADV–20]/100}
.
Lead Freq Drop [ADV–21]: PID Hi Hz Limit [SET–23] drop value with [ADV–22] at Lag pump start to prevent sys -
tem overpressure condition. Default = 10 Hz.
MMC Decel Time [ADV–22]: Sets the deceleration time for the [ADV–21] frequency drop. Default = 2 sec.
Lag Stop Freq [ADV–23]: When the Lead runs below this frequency, it sets the first condition for stopping
Lag pumps. Default = 35 Hz.
Lag Stop Delay [ADV–24]: Sets a delay time to stop Lag pump when both frequency and pressure condi -
tions are met. Default = 4 sec.
Lag Stop Level [ADV–25]: Sets a percentage above
PID F/B Max [SET–20]
(pressure) to calculate
MMC At Setpoint
as the second condition for stopping a Lag pump. Default = 0.3%.
MMC At Setpoint
=
[SET–21] + {[SET–20] x [ADV–25]/100}
.
Lead Freq Bump [ADV–26]: PID Lo Hz Limit [SET–22] increase value with [ADV–27] at Lag pump stop to prevent
system underpressure condition. Range is 0 to [SET–23]*0.4. Default = 0 Hz.
MMC Accel Time [ADV–27]: Sets the acceleration time for the [ADV–26] frequency bump. Default = 2 sec.
Lag Pump Start sequence: If the Lead motor runs at a speed equal or greater than
[ADV–18]
with system
pressure less than MMC Below Setpoint for [ADV–19] delay, the VFD will decrease PID High Freq Limit [SET–23] by
[ADV–21]
value for
[ADV–22]
time and then activate relay output to start the first Lag Pump in sequence. After
a non-adjustable 1 sec delay, the VFD will change [SET–23] to its original value and check for Lag Start/Stop
conditions. If demand is still high, the VFD will repeat Lag Start sequence for additional Lag pumps.
Lag Pump Stop sequence: If the Lead motor runs at a speed equal or less than [ADV–23] with system pres -
sure equal or greater than
MMC At Setpoint
for
[ADV–24]
delay, the VFD will increase
PID Lo Hz Limit [SET–22]
by
[ADV–26] value for [ADV–27] time and then it will deactivate relay output to stop the first Lag Pump. After a
non-adjustable 1 sec delay, the VFD will change
[SET–22]
to its original value and check for Lag Start/Stop
conditions. If demand is still low, the VFD will repeat Lag Stop sequence for additional Lag pumps. If all Lag
pumps are stopped, the VFD will check for Sleep Mode conditions.
If the VFD run command is removed during MMC operation, all Lag pump relays will deactivate in sequence
with a 1 sec delay between each relay. The delay will protect from voltage surges in the power line when Lag
pumps stop. The VFD will then stop the Lead based on the selected method (Decel or Coast).
If the VFD trips on a fault during MMC operation, the VFD will immediately deactivate all Lag pump relays
and it will coast stop.