AB Quality Allen-Bradley 1394, User Manual

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Publication 1394-5.0 — May 2000
A-6 Specifications
Input Transformer for 24V Control Power
You can use any general purpose transformer with the following
ratings.
If the input volt-amperes is more than 350 VA, adjust the load
regulation to make the transformer leakage the same as or greater than
the 250 VA transformer with 2% regulation.
User-Supplied 5V Auxiliary Encoder Power Supply
The table below shows the requirements for the 5V encoder that you
can supply. If you use an encoder that requires more than 5V, you still
need a 5V power supply for the 1394 encoder board electronics at a
rating of 0.325A (applies to 1394x-SJTxx-C, -L, and -T systems
only).
Circuit Breakers
While circuit breakers offer some convenience, there are limitations
for their use. Circuit breakers do not handle high current inrush as
well as fuses. The 1394 system needs to be protected by a device
having a short circuit interrupt current rating of the service capacity
provided or a maximum of 100,000A.
If an upstream circuit protection device is rated for the overload
current and short circuit rating, a supplementary circuit protection
device (such as the 1492) can be used as the only 1394 branch circuit
protection device. The upstream fully rated device let-through must
be less than or equal to the 10 kA interrupt rating of the 1492.
The wiring interconnection in Figure A.1 and Figure A.2 provide
examples of the needed protection and follows UL and NEC codes.
Full compliance is dependent on final wiring design and installation.
The requirements for: For a 480V system is: For a 360V system is:
Input volt-amperes 200 to 259 VA 200 to 259 VA
Input voltage 480V RMS 360V RMS
Output voltage 24V RMS 24V RMS
Load regulation 2 to 5% 2 to 5%
The: For 5V logic input power must be:
Rating 5V DC +/- 5%
Current 0.325A plus the requirement of each encoder used. For
example, if you use one encoder with a 0.2A
requirement, the supply required is 0.525A (0.325A +
0.2A = 0.525A)