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You'll need to control the motor with a large, three-pole relay, called a "contactor". If the motor is of significant size, you'll need a special kind of contactor called a motor starter (or motor protector). This is a current-protected contactor with current-based heaters sized appropriately for the motor load. They allow for the high starting currents typical of inductive motor loads and provide protection at lower currents as the motor runs.
Contactors and motor starters will have a coil voltage that's typically 24VAC, 120VAC or 208VAC. That control voltage will be switched through the single pole, normally open points of the time clock. All electro-mechanical time clocks will be able to deal with most any control voltage. Some newer solid state time clocks may not be rated to 120VAC or 208VAC so you'll need to verify the control voltage of one when deciding on the other.
A number of companies in the U.S. make contactors and motor starters: Cutler Hammer, Allen Bradley (Rockwell) and Square D are a few well known brands in the States. Other manufacturers (Siemens, et al) are more prevalent in other countries. Check with an industrial electrical supply or commercial equipment and motor supply like W.W. Grainger.
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Why can a run capacitor with a single phase motor remain in circuit after the motor starts?
Because from the capacitor characteristics at first it will charge and then it will stsrt to run so when the motor get power from single phase capacitor take time for charging. Amit.
How do you calculate 3 phase motor kWH where voltage are 440 and amps are 11?
To calculate kWh a time component is needed for the hours.
Where can you get a free wiring diagram for a 480 volt reversible motor?
If the motor is 3-phase (it will say so on the nameplate), you don't need a diagram. just hook up all 3 wires in any order. If the motor runs the wrong direction, swap any two of the phases. This is true for all 3-phase motors. Its that simple! Warning: this obviously will only work if you have 480v, 3-phase power available. If you are trying to do this at home, it almost certainly won't work, because homes (in the US) typically have 240v 1-phase power. Trying to run a 3-phase motor directly on single phase power will destroy it. There are various ways to convert single phase power to three phase, but if you are having a hard time just hooking up the motor, they are beyond your ability at this time. Get a qualified electrician to help you! It could save your motor, and quite possibly your life!
What is a single pole double throw time clock?
A single pole double throw time clock is just a time clock that has the capabilities of opening/breaking up-to two legs of a given circuit. For example ( a 208 volt, 240 volt, 277 volt ) circuit that needs to have both phase conductors isolated by means of mechanical switching. You can use it to also control two separate 120 volt circuit as well as long as the neutral does not need to be opened/broken by the time clock.
How do you connect 480 vac three phase power to a 480 vac single phase transformer?
If the primary and the secondary windings of the three phase transformer are connected in delta, you cannot get a healthy neutral from it but why bother? You simply drive a rod into earth and use it as a neutral. Alternatively either the primary or the secondary windings must be connected as star and you use the common point as neutral.
How do you wire 3 phase power to 1 phase power diagram?
In an emergency and for a short period of time you can single phase a three phase motor but the motor will be loud, have terrible power characteristics and depending upon the use will burn up rather quickly. You should never try to run this in other than a life threatening emergency situation, the motors are not designed for it. Normally you don't. <<>> A three phase motor will not start on single phase. If the motor was started on three phase and loses a phase, it will stay running at a lower percentage of efficiency. Now a days the motor protection will not let a three phase motor run in a single phasing condition. All three phase legs of the motor are monitored and in a single phase condition the other two legs of the motor draw a higher current. This higher current is sensed by the motor's overload heaters in the motor's contactor and take the motor off line by opening the motor contactor. Now to the question, any two legs of a three phase system in electrical terms is known as single phase. As long as the three phase voltage matches the voltage needed in the single phase power diagram it can be connected to operate single phase equipment.
Why can a run capacitor with a single phase motor remain in circuit after the motor starts?
Because from the capacitor characteristics at first it will charge and then it will stsrt to run so when the motor get power from single phase capacitor take time for charging. Amit.
What other features does a clock have?
It depends on the make and model of the clock. Some other features could be; The day and date. Temperature. Moon phase. Time in other zones
Can you connect a 3 phase motor to a 1 phase supply?
Single phase to three phaseThe physical internal windings between single phase and three phase motors makes this an impossibility That being said money can make anything happen. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Other wise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start.Some 3 phase motor speed controllers can be run off a single phase supply, this caused us a problem at work when a new speed control was fitted to some laundry equipment, as we then had to rewire the supply to bring in a nuetral, so i suggest a speed controller is probably the solution.
In a star-delta starter what could be the problem if the motor does not rotate in star but rotates in delta?
One of the three phase contacts in the star contactor could be burned open or just open not allowing the motor to start because of a single phase condition. The time interval between star and delta connections could be small enough that the motor heaters will not catch the single phase condition and trip. When the motor goes into delta (which is now across the line starting) all of the three phase contacts in the contactor close and the motor starts.
What happens if you connect a 9.6 v battery to a motor rated for 7.2 v?
The motor will run at a higher rate of speed than normal. The extra voltage will in time destroy the motor.
What size time delay fuse do you use on a 40 hp 230 volt 3 phase motor?
The electrical code book states that a 40 HP 230 volt three phase motor draws 104 amps. For that motor the wire must be rated for 131 amps, Non time delay fuses at 300 amps, time delay fuses at 175 amps or a 250 amp circuit breaker. When calculating wire sizes and motor protection the motor's full load amperage should be taken from the motor's nameplate.
What is the purpose of single phase preventors used in motors starters?
Phase monitors are used to detect single phasing, or loss of one phase of power from a three phase system. Most of the time they are used on very expensive motors such as high horsepower. They will shut down the starter, therefore shutting down the motor if all three phases are not available. One cause of this would be if there are three separate fuses protecting the motor and only one of them blows. The reason they are needed is because if you only send two phases to a three phase motor, it has a good chance of burning out the motor.
Can you connect a 120v 60hz clock radio purchased in US to a UK 230v 50hz supply?
Even if you used an adapter to convert the voltages the clock would run slow. Clocks are frequency dependant to keep time. Older clocks used a synchronous motor to move the dial around and newer clocks use a frequency crystal to keep the digital numbers on the readout advancing. So as you can see by connecting to a lower frequency the clock will operate slower.
What will happened if one phase loss in three phase motor?
The motor will hum and act like it is trying to run it's commonly known as single phasing, it will also heat up quite rapidly and if you set up your circuit correctly and have the proper thermal overload protection on it it will trip and protect the circuit and the motor. If the problem is in the motor winding you will have to rewind the motor or replace it
What is the probability of wiring a three phase motor rotation right the first time?
Since it can only rotate two directions, the chance is 50%. There are rotation indicators you can buy to check the phase sequence.
How can you include phase failure relay in your star delta motor starter circuit?
The star delta motor starter circuit has to have a control voltage to energize the motor magnetic contractors. A phase failure relay monitors all three phases of the incoming supply lines. The phase failure relay also has auxiliary contacts on it. There are usually two sets of "C" form contacts. The control voltage for the starter circuit must be connected across the normally open (N.O.) contacts of one of these two sets. When the phase monitor is energized these N.O. contacts close supplying the control voltage to the circuitry of the star delta starters. If there is a phase interruption, phase reversal or phase loss, the phase failure relay will de-energize and the N.O. contacts will go back to their de-energized state. If the star delta motor starter is in use at the time, its control circuitry voltage will be lost and the delta motor magnetic contactor will open. The opening of this contactor will disconnect the motor from the failed three phase supply.
