Danfoss VLT CDS 302 User Manual Download

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Initial Trouble Shooting (visual inspection of the installation)

This list shows a variety of conditions that
should be inspected visually as a part of initial
troubleshooting.

Display: Warnings, alarms, drive status; fault
history and many other items are available on the
local control panel of the drive.

Check for loose connections. Check for proper fusing. Check for blown fuses.

Avoid routing motor wiring. AC line wiring and
signal wiring in parallel. If parallel routing is
unavailable, try to maintain a separation of 15-

20cm between the cables or separate them with
a grounded conductive partition. Avoid routing
cables through free air.

Look for peripheral equipment such as switches
or input fuses circuit breakers that may be in the
input power side of the drive or output side of
the motor. Examine operation and condition of

these items as possible causes for operational
faults. Check function and installation of pressure
sensors or temperature sensors etc. used for
feedback to the drive.

Check the operational status of all cooling fans.
Check for blockage or constrained air passages.

Drive interior must be free of dirt, metal, chips,
moisture and corrosion. Check for burnt or
damaged power components or carbon deposits
that were the result of a disastrous component

failure. Check for cracks or breaks in the housing
of the power semiconductors or pieces of broken
components housing loose inside the unit.

Check for proper installation with regards to
electromagnetic capability. Refer to the CDS
manual, in the chapter “How to install” and then

“ Electrical Installation – EMC Protection “ for
further details.

Look for unusual amounts of vibration to which
the drive may be subject. The drive should be

mounted solidly or the use of shock mounts
employed.

Under specific conditions these units can
be operated within a maximum ambient
temperature of 50°C (24h average maximum

45 °C). Humidity level must be less than 95%
non-condensing. Check for harmful airborne
contaminates such as sulphur based compounds.

These drives require a top and bottom clearance
of 10cm to ensure proper airflow for cooling.

Drives with exposed heat sinks out the back of
the drive must be mounted on a flat solid surface.

Check for loose connections. Check for switching
components in the output circuit. Check for
faulty contacts in the switch gear.

The drive requires a dedicated ground wire
from its chassis to the building ground. It is also
suggested that the motor be grounded to the
drive chassis. The use of conduit or mounting

of the drive to a metal surface is not considered
a suitable ground. Check for good grounding
connections that are tight and free of oxidation.

Check for broken or damaged wires and
connections. Check the voltage source of the
signals. Though not always necessary depending

on the installation condition, the use of shield
cable or a twisted pair is recommended. Ensure
the shield is terminated correctly.

Check that the drive parameter settings are
correct according to the motor, application and
I/O configuration.

Check nameplate of the Compressor. Ensure the
compressor matches the drive. Check that drive’s

compressor par. 1-13 is set according to the
compressor e.g.:

Input power wiring

Cable routing

Peripheral equipment

(sensors, contactors, etc)

Trip on over Temperature

Drive interior