20
6.2 - Power supply
The power supply must conform to the specification on the
chiller nameplate. The supply voltage must be within the
range specified in the electrical data table. For connections
refer to the wiring diagrams.
WARNINg: Operation of the chiller with an improper
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 chiller 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 below.
The calculations are based on the maximum machine current
(see electrical data tables). For the design the following
standardised installation methods are used, in accordance
with IEC 60364, table 52C:
•
For units installed inside the building:
No.13: perforated horizontal cable conduit, and No.
41: closed conduit.
The calculation is based on PVC or XLPE insulated cables
with copper or aluminium core. A maximum ambient
temperature of 40°C has been taken into account. The
given wire length limits the voltage drop to < 5%.
IMPORTANT: Before connection of the main power cables
(L1 - L2 - L3) on the terminal block, it is imperative to
check the correct order of the 3 phases before proceeding
to the connection on then terminal block or the main
disconnect/isolator switch.
6.4.1 - selection table of minimum and maximum wire sections for connection to 30Rw/Rwa units
400 V-3 ph-50 hz
30RW/30RWA
Minimum wire
section (mm
2
)
Wire type
l (m)
Maximum wire
section (mm
2
)
Wire type
l (m)
020
1x 6
XLPE Cu
85
1x16
PVC Al
160
025
1x 6
XLPE Cu
80
1x16
PVC Al
155
030
1x 6
XLPE Cu
80
1x16
PVC Al
150
040
1x 6
XLPE Cu
75
1x16
PVC Al
145
045
1x 6
XLPE Cu
75
1x16
PVC Al
145
060
1x 10
XLPE Cu
90
1x25
PVC Al
165
070
1x 10
XLPE Cu
90
1x35
PVC Al
185
080
1x 16
XLPE Cu
110
1x35
PVC Al
185
090
1x 16
XLPE Cu
108
1x50
PVC Al
215
110
1x 25
XLPE Cu
135
1x70
PVC Al
230
120
1x 25
XLPE Cu
130
1x70
PVC Al
230
135
1x 35
XLPE Cu
145
1x95
PVC Al
250
150
1x 35
XLPE Cu
145
1x95
PVC Al
250
160
1x 35
XLPE Cu
142
1x120
PVC Al
260
185
1x 50
XLPE Cu
162
1x120
XLPE Al
205
210
1x 70
XLPE Cu
175
1x120
XLPE Al
205
245
1x 70
XLPE Cu
170
1x150
XLPE Al
210
275
1x 70
XLPE Cu
168
1x150
XLPE Al
210
300
1x 95
XLPE Cu
180
1x185
XLPE Al
220
S Power supply wire section (see diagram in chapter ‘Electrical connection’).
Motor
