Trane Force Flo Cabinet Heater - MCA and MOP Calculations

Installation - Electrical
UNT-SVX07E-EN 81
MCA and MOP Calculations
Minimum circuit ampacity (MCA) and Maximum
Overcurrent Protection (MOP) calculations for units with
single-phase electric heat:
Heater amps = (heater kW x 1000)/heater voltage
Note: Use 120 V heater voltage for 115 V units. Use 240 V
heater voltage for 230 V units.
MCA = 1.25 x (heater amps + all motor FLAs)
MOP = (2.25 x largest motor FLA) + second motor FLA +
heater amps (if applicable)
Select a standard fuse size or HACR type circuit breaker
equal to the MCA. Use the next larger standard size if the
MCA does not equal a standard size.
Standard fuse sizes are: 15, 20, 25, 30, 35, 40, 45, 50, 60
amps
Fan-coil electric heat MBh = (heater kW) (3.413)
Table 33. Electric heat kW, low vertical fan-coil
Unit Size Unit Voltage kW kW kW kW
3.0 115 1.00 1.50 2.00
4.0 115 1.00 1.50 2.00 2.50
6.0 115 1.00 1.50 2.00 2.50
Note: Low vertical units are only available with electric heat in combination
with the two-row cooling coil.
Table 34. Force-Flo single-stage, max kW electric heat
Unit
Size
Voltage # Wires Heater kW
Heater amps/
ph
02
208/60/1 2 2.25 10.90
240/60/1 2 3.00 12.50
277/60/1 2 3.00 10.90
208/60/3 3 2.25 6.30
240/60/3 3 3.00 7.30
480/60/3 4 3.00 3.70
03
208/60/1 2 4.50 21.70
240/60/1 2 6.00 25.00
277/60/1 2 6.00 21.70
208/60/3 3 4.50 12.60
240/60/3 3 6.00 14.50
480/60/3 4 6.00 7.30
04
208/60/1 2 5.70 27.50
240/60/1 2 7.50 31.30
277/60/1 2 7.50 27.10
208/60/3 3 5.70 15.90
240/60/3 3 7.50 18.10
480/60/3 4 7.50 9.10
06
208/60/1 2 7.90 38.00
240/60/1 2 10.50 43.80
277/60/1 2 10.50 38.00
208/60/3 3 7.90 21.90
240/60/3 3 10.50 25.30
480/60/3 4 10.50 12.70
Note: All data based on individual units. Electric heat will operate only with
fan at high speed.
Table 35. Force-Flo single stage, low kW electric heat
Unit
Size
Voltage
#
Wires
kW
amps
/ph
kW
amps
/ph
kW
amps
/ph
02
208/60/1 2 0.8 3.7 1.5 7.3
240/60/1 2 1.0 4.2 2.0 8.4
277/60/1 2 1.0 3.7 2.0 7.3
03
208/60/1 2 2.3 10.9
240/60/1 2 3.0 12.5
277/60/1 2 3.0 10.9
208/60/3 3 2.3 6.3
240/60/3 3 3.0 7.3
480/60/3 4 3.0 3.7
04
208/60/1 2 2.3 10.9
240/60/1 2 3.0 12.5
277/60/1 2 3.0 10.9
208/60/3 3 2.3 6.3
240/60/3 3 3.0 7.3
480/60/3 4 3.0 3.7
06
208/60/1 2 2.3 10.9 3.3 15.9
240/60/1 2 3.0 12.5 4.5 18.8
277/60/1 2 3.0 10.9 4.5 16.3
208/60/3 3 2.3 6.3 3.3 9.2
240/60/3 3 3.0 7.3 4.5 10.9
480/60/3 4 3.0 3.7 4.5 5.5
08
208/60/1 2 2.3 10.9 3.3 15.9 4.5 21.7
240/60/1 2 3.0 12.5 4.5 18.8 6.0 25.0
277/60/1 2 3.0 10.9 4.5 16.3 6.0 21.7
208/60/3 3 2.3 6.3 3.3 9.2 4.5 12.5
240/60/3 3 3.0 7.3 4.5 10.9 6.0 14.5
480/60/3 4 3.0 3.7 4.5 5.5 6.0 7.3
10
208/60/1 2 2.3 10.9 3.3 15.9 5.7 27.5
240/60/1 2 3.0 12.5 4.5 18.8 7.5 31.3
277/60/1 2 3.0 10.9 4.5 16.3 7.5 27.1
208/60/3 3 2.3 6.3 3.3 9.2 5.7 15.9
240/60/3 3 3.0 7.3 4.5 10.9 7.5 18.1
480/60/3 4 3.0 3.7 4.5 5.5 7.5 9.1
12
208/60/1 2 2.3 10.9 3.3 15.9 6.6 31.8
240/60/1 2 3.0 12.5 4.5 18.8 9.0 37.5
277/60/1 2 3.0 10.9 4.5 16.3 9.0 32.5
208/60/3 3 2.3 6.3 3.3 9.2 6.6 18.4
240/60/3 3 3.0 7.3 4.5 10.9 9.0 21.7
480/60/3 4 3.0 3.7 4.5 5.5 9.0 10.9
Note: All data based on individual units.