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Triple (3) Ametek lamb 6.6 vacuum motors (122234-18) in series VS parallel
Single vacuum unit rating 131.8" of lift X 138.8 cfm = 18,293 vacuum units
Average amp draw is 11.1 @ 120 volts (max amps is 14 with the carpet cleaning wand off the floor)
3 motors in series:
Inches of lift 131.8 + 92.3 (70% of the unit in front of it) + 64.6 (70% of the unit in front of it.) = 288.7"
Cfm 138.8 + 34.7 (25% of the unit in front of it) + 8.7 (25% of the unit in front of it) = 182.2 cfm
Vacuum units 288.7 X 182.2 = 52,601
3 motors in parallel:
Inches of lift 131.8 + 2% for parallel = 134.4"
CFM 138.8 X 3 = 416.4
Vacuum units 134.4 X 416.4 = 55,964
So now look at the Goliath quad 6.6 with one motor turned off. This is two in series and one in parallel.
Two thirds the machine is performing at 224.1" with up to 173.5 cfm
One third is performing at 131.8" and 138.8 cfm
Combined is 177" @ 311 cfm = 55,047 vacuum units
In summary please note that the heat that is expelled in the exhaust of the vacuum motors also goes up by 25% with each motor in series.
This is the reason that the Goliath heat exchanger option works well. 140 degree exhaust with one motor goes to 175 degree with two vacuum motors. Place a third in series adds 9 degrees to 184 degrees. The maximum temperature for bearing life is 180 degrees F. I am sure if we check with the factory they will tell you that just might shorten the life of the bearings. The third motor might have to be changed a little sooner than the rest.
You can see that the worst option is to place all the vacuum motors in series in a 3 or 4 motor pattern.
Donald Cook
Single vacuum unit rating 131.8" of lift X 138.8 cfm = 18,293 vacuum units
Average amp draw is 11.1 @ 120 volts (max amps is 14 with the carpet cleaning wand off the floor)
3 motors in series:
Inches of lift 131.8 + 92.3 (70% of the unit in front of it) + 64.6 (70% of the unit in front of it.) = 288.7"
Cfm 138.8 + 34.7 (25% of the unit in front of it) + 8.7 (25% of the unit in front of it) = 182.2 cfm
Vacuum units 288.7 X 182.2 = 52,601
3 motors in parallel:
Inches of lift 131.8 + 2% for parallel = 134.4"
CFM 138.8 X 3 = 416.4
Vacuum units 134.4 X 416.4 = 55,964
So now look at the Goliath quad 6.6 with one motor turned off. This is two in series and one in parallel.
Two thirds the machine is performing at 224.1" with up to 173.5 cfm
One third is performing at 131.8" and 138.8 cfm
Combined is 177" @ 311 cfm = 55,047 vacuum units
In summary please note that the heat that is expelled in the exhaust of the vacuum motors also goes up by 25% with each motor in series.
This is the reason that the Goliath heat exchanger option works well. 140 degree exhaust with one motor goes to 175 degree with two vacuum motors. Place a third in series adds 9 degrees to 184 degrees. The maximum temperature for bearing life is 180 degrees F. I am sure if we check with the factory they will tell you that just might shorten the life of the bearings. The third motor might have to be changed a little sooner than the rest.
You can see that the worst option is to place all the vacuum motors in series in a 3 or 4 motor pattern.
Donald Cook