Q1.. Why is it that switch's are rated by their ith amps and not by the switch contactors amp capacity?
Q2..When choosing a switch for induction motors should we choose by AC3 or AC23 amp rating?
Q3..Why do some spec sheets only give a Kw rating for AC3 ?
Q4..Why do specs give a Kw rating when the switch's AC3 amp rating is well under what that size motor amp draw is?
Q5..What does it mean when the switch has a rating like this 250v 16(12)a ?
Q6..On spec sheets under Power P (KW) AC3 has this under 240v .. 3/2.2 and under 440v ... 5.5/3 what do these numbers represent?
Q7..if a contactor and thermal overload relay is used can a switch of a lesser ac3 amperage be used?IE:-Does the contactor and relay reduce the amp draw on a switch? and if so what is the formula?
Q7... example
Q9... In the example above if I wanted to run a 1 phase 240 vac 4kw 18.2 amp induction motor I would need to use YMW-26-32?
Q2..When choosing a switch for induction motors should we choose by AC3 or AC23 amp rating?
Q3..Why do some spec sheets only give a Kw rating for AC3 ?
Q4..Why do specs give a Kw rating when the switch's AC3 amp rating is well under what that size motor amp draw is?
Q5..What does it mean when the switch has a rating like this 250v 16(12)a ?
Q6..On spec sheets under Power P (KW) AC3 has this under 240v .. 3/2.2 and under 440v ... 5.5/3 what do these numbers represent?
Q7..if a contactor and thermal overload relay is used can a switch of a lesser ac3 amperage be used?IE:-Does the contactor and relay reduce the amp draw on a switch? and if so what is the formula?
Q7... example
- Dual Voltage: 110V/220V; Single Phase
- Rated Current: 2 HP / 35 Amps at 120V; 3 HP / 20 Amps at 230V .....Why can this switch only run a 3hp (2.2kw) motor if it is rated at 20 amps at 230v if a 4hp (3kw) motor has a max draw of 18.2 amps at 230v? Why can it not be used on a 4hp(3kw) motor?
Q9... In the example above if I wanted to run a 1 phase 240 vac 4kw 18.2 amp induction motor I would need to use YMW-26-32?
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