33
DC Power Supply Precautions
The following precautions must be observed when installing the chassis model with
an internal DC power supply.
1.
Check nameplate ratings to ensure there is no overloading of supply circuits that
could affect over current protection and supply wiring.
2.
In addition, the following must be observed:
a.
Connect the equipment to a 36 to 56.7 V DC power source that is
electrically isolated from the alternating current source.
Nominal
Voltage
Minimum
Voltage
Maximum
Voltage
Transient
Voltage
48 36 56.7
75.0*
* 75.0-V transient with a duration of 10.0 ms with a rate of rise and fall of
10 V/ms. The equipment shall meet its operational specifications during
the transient.
b.
Route input wiring to terminal block and secure in such a manner that it is
protected from damage and stress. Do not route wiring past sharp edges or
moving parts.
c.
Incorporate a readily accessible disconnect device, with a 3mm minimum
contact gap in the fixed wiring.
d.
Install only in Restricted Access Areas (dedicated Equipment Rooms,
Equipment closets or the like) in accordance with Articles 110-18, 110-26,
and 110-27 of the National Electric Code, ANSI/NFPA 70.
e.
Provide a listed circuit breaker suitable for branch circuit protection of the
wiring and rated maximum 1A @ 48 V DC.
f.
For supply connections, use wires suitable for at least 75° C.
