Mammoth 800 to 5500 CFM: Dedicated Outdoor Air System with Enthalpy Wheels (VHC) - Manual (Page 26)

MAMM-VHC-IOM-1A (JANUARY 2013) 26
Minimum Current Ampacity (MCA)
Calculation
1.25 x FLA of larger hp motor or compressor = _____
1.25 x heater FLA = + _____
Sum of all other motors FLA = + _____
Wheel drive motor and standard controls FLA = + _____
Calculated total MCA = _____
Maximum Overcurrent Protection (MOP)
Calculation
2.25 x FLA of larger hp motor or compressor = _____
Electric heater FLA = + _____
Sum of all other motors FLA = + _____
Wheel drive motor and standard controls FLA = + _____
Calculated total MCA = _____
Actual MOP (from Table E5) = _____
Finding the Actual MOP Value
From the calculated MOP value, select the next smallest
value of protection from the Standard Overcurrent Protec-
tion chart below to get the actual MOP value (maximum
value of overcurrent device).
IMPORTANT
If this method leads to an actual MOP value being smaller
than the calculated total MCA, then a larger value must
rather be selected, such that the actual MOP is at least
equal to the calculated total MCA.
Table E4:
For Dual Circuit On/off Units
6 tons
Two 3 ton on/off compressors
8 tons Two 4 ton on/off compressors
10 tons Two 5 ton on/off compressors
12 tons Two 6 ton on/off compressors
14 tons Two 7 ton on/off compressors
16 tons Two 8 ton on/off compressors
21 tons Two 10 ton on/off compressors
For Dual Circuit VRC ® Units
6 tons
One 3 ton on/off compressor
One 3 ton VRC compressor
8 tons
One 4 ton on/off compressor
One 4 ton VRC compressor
10 tons
One 5 ton on/off compressor
One 5 ton VRC compressor
12 tons
One 6 ton on/off compressor
One 6 ton VRC compressor
14 tons
One 7 ton on/off compressor
One 7 ton VRC compressor
16 tons
One 8 ton on/off compressor
One 8 ton VRC compressor
21 tons
One 10 ton on/off compressor
One 10 ton VRC compressor
Table E5: Standard Overcurrent Protection
3 40 250
4 45 300
5 50 350
6 60 400
7 70 450
8 80 500
9 90 600
10 100 650
12 110 700
15 125 750
20 150 800
25 175 850
30 200 900
35 225 1,000