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

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OPERATION
Protection Features
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4. While running at the motor at minimum frequency, determine whether VFD trips on HLD:
• If system trips on HLD using default HLD Level [Set–48], increase level by 3% until system does not
trip.
• If system does NOT trip using default HLD Level [Set–48], decrease the level by increments of 3%
until system trips, then increase back by 3%.
5. If nuisance tripping occurs, increase HLD Min Torque [Prot–58] by increments of 1%.
6. Adjust HLD Delay [Set–50] to duration acceptable for operation.
Underload Protection (Dry Well or Belt Loss)
Underload Detection (ULD) monitors motor current and frequency to protect against conditions such as a
dry well, broken pump, or broken drive belt. Two options are available:
•
ULD by Current: The VFD trips when current reading is less than set value and speed is equal or greater
than set value, the VFD will trip on ULD.
• ULD by Torque: The VFD calculates an Underload Torque
Limit curve across the full frequency range based on motor
parameters, VFD Base Frequency, and ULD settings. The VFD
then trips when torque falls below this curve with frequency
equal to or greater than
ULD Freq [SET-43] for a duration of ULD
Delay [SET-44]
. This feature is primarily used for centrifugal
loads such as centrifugal pumps or fans. It is not recom -
mended for progressive cavity pumps or constant torque
loads.
To enable Underload Protection, adjust the following parameters:
Prime Time [IO–39]: Some pump applications require time for
the pump to self-prime before the load stabilizes. This setting
adds a 0 to 6000 second delay before the VFD starts monitoring
for Underload or No-Flow conditions, which protects against nuisance faults. The delay operates at any VFD
start, in both Hand and Auto modes, including Run, Wake, Restart, or Reset commands.
ULD Select [SET–41]: Disable, By Current, or By Torque.
ULD Min Torque [PROT–57]: If using ULD by Torque, set minimum torque level percentage at 0 Hz. Default
= 10%.
ULD Level [SET–42]: For ULD by Current, set as a percentage of motor FLA (SFA) (default = 45%). For ULD
by Torque, set as a percentage of nominal torque at base frequency. If all conditions are met, VFD will trip
below this level.
ULD Frequency [SET–43]: Set minimum frequency for ULD by Current or Torque detection.
ULD Delay [SET–44]: Delay range from 1 to 360 seconds (default = 2 sec). When timer expires, if current is
still below [Set–42] or torque is still below ULD Torque Limit curve and frequency is still above [Set–43],
VFD will trip based on [Set–41].
ULD Recovery Time [SET–45]: 0 to 720 min (default = 30 min). If timer is set to value greater than 0 min -
utes, VFD will restart after timer expires. If set to 0 and the VFD trips, manual or remote reset is required (no
auto retries).
For dry well protection,
Recovery Time
should be long enough to allow the well to be filled. If VFD trips
the first time on Underload, it will restart after the Recovery timer expires. If VFD trips again, the timer
value will be doubled. The VFD will continue restart attempts, doubling the timer value until it reaches
720 minutes (12 hours). Then every restart will be in 720 min.
ULD Recover Cnt [SET–46] displays the
countdown before the next restart attempt.
When VFD finally runs without tripping for 180 sec, the recovery timer will be reset to original setting
and at next underload trip VFD will wait for well fill for original [Set–45] time value.
Nominal Torque
Percent
Nominal Torque Load
Underload Torque
Limit
Base Freq VFD-02 ULD Freq SET-43
ULD Level SET-42
ULD Min PROT-57
Nominal Torque 100%
Nominal Torque
Percent
Nominal Torque Load
Underload Torque
Limit
Base Freq VFD-02 ULD Freq SET-43
ULD Level SET-42
ULD Min PROT-57
Nominal Torque 100%