Tronair 112850D0000, Operation & Service Manual

Page: 12 / 57

28.5 VDC Ground Power Unit
Models 112850S0000 112850S0100 112850S0200
112850D0000 112850D0100/AV 112850D0100-A5 112850D0200
112860S0000 112860S0100 112860S0100-A4 112860S0100-A6 112860S0200
112860D0000 112860D0100 112860SD100-A5 112860D0200 112860SD200-A5
06/2013 | Rev. 03 Page | 9
4.5
ELECTRICAL CONNECTIONS (POWER) (continued)
4.5.2 Cable Sizing
Cables should be sized in accordance with the rating of the next protective device upstream , taking into account
temperature, voltage-drop and installation method factors, as per the appropriate standard for the site. In general, Tronair
recommends that the voltage-drop for both input and output power cables should not exceed 1.5%, and that the connecting
cables should be as short as possible especially the output cable (less than 10 m/30 feet is recommended). Tronair should be
consulted if these requirements cannot be met.
When specifying the cable lengths allow for about 0.5 m/20 in. inside the cubicle. The table on the following page shows the
recommended cable types:
Equipment Type
Line
Voltage Rated
Amps
Input Cable (If Less Than 30´)/
Copper Size Output Cable
28V DC GPU 600A 208 56 1 x NYY 4 x 10 RE/10 or #4 2 x NYY 120 or 2x 4/0 cables
230 51 1 x NYY 4 x 10 RE/10 or #4
400 29 1 x NYY 4 x 6 RE/6 or #8
480 24 1 x NYY 4 x 4 RE/4 or #8
575 20 1 x NYY 4 x 4 RE/4 or #8
4.5.3
Mains Fuses
To meet Health & Safety requirements, lockable isolating fused-switches must always be installed for the mains infeed. The
fuses should be of type GL. Likewise, it should be possible to isolate the converter output from downstream circuits by means
of an external lockable switch or circuit breaker. Please consult your Tronair representative regarding use of circuit breakers
for the mains infeed.
Equipment Type Mains Isolator CB
28V DC GPU 600A 100 A 25 A, 5A
4.5.4 Connections
Power:

3 phase Mains Neutral

2 wire 28V DC + and
–
The terminal arrangement will depend on the size and configuration of the 28 VDC GPU. The following drawings show the
various configurations:
Terminal No. of Terminal Function Short Name
L1 Mains Input L1
L2 Mains Input L2
L3 Mains Input L3
N50/N60 Mains Neutral N50
+ Load
Load Output -