# MCA, MFA, MOP, MSC and TOCA



## Shockdoc

Sounds like an AC compressor nameplate.


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## guitarboyled

That's exactly what it is!


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## Shockdoc

guitarboyled said:


> Minimum Circuit Amps or Minimum Circuit Ampacity (MCA) 41.3 Amps
> Maximum Fuse Amps (MFA) 60 amps
> Maximum Overcurrent Protection (MOP)
> Maximum Starting Current (MSC) 155 amps
> Total Overcurrent Amps (TOCA) 54.5 amps
> 
> Here we go…
> 
> I’m guessing that MCA is the ampacity required while the motor is running
> 
> The MFA and MOP are the required protection for that motor, I presume we select the next available breaker or fuses. By the way, what’s the difference between MFA and MOP?
> 
> MSC is the ampacity required at the startup of the motor. My question with this one is why doesn’t that extra demand (155 amps is superior to 60 amps) doesn’t trip the breaker or blow the fuses?
> 
> The TOCA I have no idea what that is.


It won't trip the breaker as long as it's a HACR rated breaker (which almost every breaker is) that will allow a 30 second surge to occur for start up. Time delay or Slow blow fuses are used when a fused system is utilized for the same reason. If the circuit is easy it is always better to run the maximum overcurrent sized circuit .


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## NolaTigaBait

Wire a circuit that is good for 41.3 amps and fuse it at 60 amps...Thats all you really need to know.


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## guitarboyled

The startup current is required for how much time usually? Let's say in the present example for how long will the motor pull 155 amps before it idles normally at 41.3 amps?

I’m trying to figure out what the TOCA is but every link seems to point to the same manufacturer. Could it be something that’s not really use by the general electrical industry?


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