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Heat exchangers
General
The motors described in this paragraph are
similar to those already described in previous
paragraphs. The only difference is the cooling
method (code IC 86 W for air/water heat ex-
changer and IC 666 for air/air heat exchanger)
and the degree of protection that can be IP 54
or IP 55, according to customer request.
The operation of these motors requires special
care since the cooling air flows in a closed loop.
The smallest particles of carbon dust produced
by the brush wear may pass through the filter
and is circulated inside the motor and can settle
on the windings, so affecting the ground insula-
tion level. ABB recommends users to follow all
maintenance instructions described previously
and to clean the motor regularly by opening all
covers and vacuuming out all dust not held by
the filtering material.
Air/air heat
exchangers
Air/air heat exchangers are normally supplied
separately. Unless otherwise stated on the
delivery orders, the cooling equipment must
always be installed so that the cooling air enters
DMI at the N-end.
Two constant speed fans provide air circulation
for the outer and inner circuits.
Outer circuit: Ambient air is forced through the
heat exchanger by a fan. For
motors with low loads or low
ambient air temperature a thermo-
stat control is recommended.
Inner circuit: A constant speed fan circulates
the internal cooling air. Carbon
dust is filtered out by a polyamide
filter. A second filter is included
for leakage air.
Air/water heat
exchangers
A totally-enclosed motor with an air/water heat
exchanger is recommended for polluted operat-
ing environments.
The heat exchanger unit, which is supplied
separately, is located on top of the motor as
standard. Unless otherwise stated on the deliv-
ery orders, the cooling equipment must always
be installed so that the cooling air enters DMI at
the N-end (Non drive-end).
Outer circuit: As seen from the drive end, the
water connection flanges are on
the left-hand side as standard.
Thermostat control is recom-
mended on motors with low loads
or a low incoming water tempera-
ture to avoid condensation in the
cooling air circuit and to minimize
water consumption.
Inner circuit: A constant-speed fan circulates
the internal cooling air. A polya-
mide filter is provided to filter out
carbon dust. A second filter is
included for leakage air.
Mounting
Mounting of IC 666 and IC 86W heat
exchangers, DMI 180-280
1. Mount the 19x4 mm gasket (item 4) on the
DMI-machine according to the figures below.
Note! The gasket must surround both holes
at the N-end.
2. Remove the covers A (and B if the heat
exchanger is equipped with it) from the heat
exchanger.
3. Place the heat exchanger on the
DMI-machine.
4. Mount the screws (item 2) and the washers
(item 3).
5. Assemble the covers A (and B if the heat
exchanger is equipped with it) on the heat
exchanger.
Note!
The max water pressure is 1 x 106 Pa (10 bar). The
max inlet water temperature is 25°C. A water tem-
perature rise of 8-13 K is to be expected