Individual circuits or one circuit for fan coils

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olc

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A small building with a half dozen or so fan coils (230V, 1Ph, 1A). If we use one circuit with a fused safety switch or circuit breaker at each unit - a good solution? (as oppose 6 separate circuits)?
Can the circuit breaker (installed adjacent to the fan coil) be the disconnect?
 
We do that all the time with much larger feeds, say a 60 amp feeder tapped at a number of 15 amp fused safety switches for HVAC equipment in office space ceilings.
 
olc said:
A small building with a half dozen or so fan coils (230V, 1Ph, 1A). If we use one circuit with a fused safety switch or circuit breaker at each unit - a good solution? (as oppose 6 separate circuits)?
Can the circuit breaker (installed adjacent to the fan coil) be the disconnect?
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Why would you need any OCPD at the FCU? Put all of them on one 15 amp circuit.
 
Do these FCU's have a maximum OCPD size listed on the nameplate? Are you saying that there limited by the manufacturer to less than a 15 amp circuit?
 
No, the manufacturer does not require short circuit protection lower than 15A. However, the literature does not specifically say they have built-in overload protection (even though I can't imagine they don't). The fan coil manufacturer's instructions do show individual fuses though.
I don't have access the an actual nameplate. (I'm talking about Daikan split system indoor units)
 
olc said:
No, the manufacturer does not require short circuit protection lower than 15A. However, the literature does not specifically say they have built-in overload protection (even though I can't imagine they don't). The fan coil manufacturer's instructions do show individual fuses though.
I don't have access the an actual nameplate. (I'm talking about Daikan split system indoor units)
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230 watts is in a transition area between small fan motors which can be "impedance protected" so that even with locked rotor they do not draw enough power to overheat and larger fan motors which generally have integral thermal overloads. It is possible that a low cost design in this area is dependent on individual fuses. Particularly true in mini-split systems where one circuit, with one OCPD, will often supply both the compressor and the fan unit.
 
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