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EC Plenum (Plug) Fans
NOTICE:
Electronically Commutated (EC) motors with backward curved
plenum (plug) fans are
a special optional
on some Mini-Plus units.
Maintenance is not required on electronically commutated (EC) motor/plenum fan modules. The motors
are sealed, have maintenance free ball bearings and permanent lubrication. The only acceptable
service is replacement.
WARNING:
Due to the use of capacitors in the electronic systems of the
plenum fan motor, danger exists even after the input power has been
switched OFF. Do not directly touch the energized parts due to the
internal circuits remain energized for a short period of time after shutdown
or due to faults. The controller housing cover may only be opened when
the input power has been switched OFF and a period of three minutes
has elapsed since switching it OFF.
Electronically Commutated Motors
WARNING:
The plug fan modules are powered by high voltage input line
power (i.e. 208-230V/3PH/60HZ or 460V/3PH/60HZ). Do not carry out
any work on electrically live parts. Even after disconnection, the de-link
circuit is still live. Always wait at least 3 minutes.
EC motors have built in protective features that include the following:
• Over-Temperature protection of the (motor) electronics,
• Over-Temperature protection of the motor,
• Locked rotor protection,
• Phase failure protection,
• Under voltage detection,
• Short circuit protection.
If any of the conditions exist, the motor stops electronically and an alarm (FAN FAILURE) will be
indicated on the unit’s controller screen.
The motor will not startup automatically. To reset, the power supply must be switched to OFF for a
minimum of twenty (20) seconds.
If for any reason the rotor is blocked, the motor will electronically switch off. Before looking for blockage
make certain to remove power from the unit. Once the blockage is cleared the motor will automatically
restart when powered ON.
If there is an alarm condition indicated as “NO AIRFLOW”, all active functions (cooling, heating and
humidification will stop until the alarm is cleared.
Summary of Contents for DA PA-04
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