How to Calculate MOCP

James Wiley

MOCP (maximum overcurrent protection) refers to the maximum allowable circuit breaker of a particular electrical unit that will correctly shut off power to equipment that is malfunctioning. MCOP is most commonly calculated for electrical heaters that are going to be installed in homes or buildings. Accurately computing MOCP values is an important safety protocol in the event of an electrical failure or problem. People near the electrical wiring or equipment could be hurt if the MOCP values of the equipment were incorrectly determined, resulting in an ineffective circuit breaker. Calculating MOCP values requires the identification of several variables usually included in the electrical heater instructions and procedures manual. They can also be obtained by calling the manufacturer.

Step 1

Determine whether the electric heater has field-installed electric heat or has single point power (contains electric heat). The formulas for the two variations are different.

Step 2

Multiply the full load amps of the indoor fan motor by 400 percent for a single-point power unit.

Step 3

Add the resulting number to the full amp loads of the heater. This will give you the MOCP for a unit with single-point power.

Step 4

Multiply the heater full amp loads by 150 percent and subtract the resulting number from 125. The end number will be the MOCP for a unit with field-installed electric heat.