29
Legend
1 Main disconnect switch
PE Earth connection
S
Power supply cable section (see table “Recommended wire sections”).
NOTES:
The 61WG/30WG/30WGA 020-090 units have only one
power connection point located at the main disconnect
switch.
Before connecting electric power cables, it is imperative to
check the correct order of the 3 phases (L1 - L2 - L3).
Non-certified drawings.
Refer to the certified dimensional drawings.
Before connecting the unit check that the phase order in the
customer control box is the same as shown in the customer
wiring diagrams.
6 - ELECTRICAL CONNECTION
6.1 - Electrical connections, control box 61WG/30WG/
30WGA
18
18
79
26
S
1
1
PE
6.2 - Power supply
The power supply must conform to the specification on the
unit nameplate. The supply voltage must be within the range
specified in the electrical data table. For connections refer to
the wiring diagrams.
In 30WGA units the power supply must not be disconnected
after the unit has been commissioned, except for quick
maintenance interventions (one day). For longer maintenance
tasks or if the unit is put into storage (for example during
the winter, when the unit is not used for cooling), the unit
power supply must be ensured to guarantee supply to the
compressor heaters on the crankcase.
WARNING: Operation of the unit with an incorrect supply
voltage or excessive phase imbalance constitutes abuse which
will invalidate the Carrier warranty. If the phase imbalance
exceeds 2% for voltage, or 10% for current, contact your
local electricity supply at once and ensure that the unit is
not switched on until corrective measures have been taken.
6.3 - Voltage phase imbalance (%)
100 x max. deviation from average voltage
Average voltage
Example:
On a 400 V - 3 ph - 50 Hz supply, the individual phase voltages
were measured to be:
AB = 406 V ; BC = 399; AC = 394 V
Average voltage = (406 + 399 + 394)/3 = 1199/3
= 399.7 say 400 V
Calculate the maximum deviation from the 400 V average:
(AB) = 406 - 400 = 6
(BC) = 400 - 399 = 1
(CA) = 400 - 394 = 6
The maximum deviation from the average is 6 V. The greatest
percentage deviation is: 100 x 6/400 = 1.5 %
This is less than the permissible 2% and is therefore
acceptable.
6.4 - Recommended wire sections
Wire sizing is the responsibility of the installer, and depends
on the characteristics and regulations applicable to each
installation site. The following is only to be used as a guide-line,
and does not make Carrier in any way liable. After wire sizing
has been completed, using the certified dimensional drawing,
the installer must ensure easy connection and define any
modifications necessary on site.
The connections provided as standard for the field-supplied
power entry cables to the general disconnect/isolator switch
are designed for the number and type of wires, listed in the
table on the next page.
Motor
Summary of Contents for 30WG 020
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