Milnor Q4G Series, Схемы/Электрические компоненты, Страница: 8 / 60

MSSM0118AE/9330BV (1 of 2)
È FUSE/CIRCUIT BREAKER AND WIRE SIZING
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Grounding
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Fuse Sizing
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Circuit Breaker Sizing
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Wire Sizing
Ê Grounding
Ground machine to an earth ground (zero potential). Use a ground wire of at least as large a gauge as that
required for incoming power; do not rely on conduit, machine anchorage, etc. Connect the ground wire between the
ground lug on the incoming power junction box on the machine and the external disconnect box or other location
as required to assure a reliable earth ground.
Ê Fuse Sizing
Size external fuses per the external fuse and wire size table in the schematic manual. The recommended fuse
sizes are per National Electric Code (NEC) section 430-52, exception No. 2 Part B, as follows:
The rating of a time-delay (dual-element) fuse shall be permitted to be increased, but shall in no case exceed
225 percent of the full-load current.
UNSAFE OPERATION AND MACHINE DAMAGE HAZARDS—Correct fuse must be used. An
extract motor may take up to two minutes to accelerate the basket to full speed, during
which time the motor draws nearly locked rotor current. All motors on dryers and mem-
brane presses may run at the same time requiring fusing for the whole group.
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NEVER use fuses other than those specified in the tables in the schematic manual.
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Use only Bussmann Fusetron FRN (up to 250V), FRS (250 to 600V) or similar lag type
fuses.
Ê Circuit Breaker Sizing
If an inverse time circuit breaker is to be used, it should have the same characteristics as FRN/FRS type fuse,
which will allow you to use the Fuse Size as shown in the table; otherwise, use the Circuit Breaker Size shown in
the table. The calculation is per National Electric Code (NEC) section 430-52, exception No. 2 Part C, as follows:
The rating of an inverse time circuit breaker shall be permitted to be increased but shall in no case exceed
400 percent for full-load currents of 100 amperes or less.
B
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