3 phase sander connection.

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petertheeater

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Acquired a horizontal belt sanding machine recently. I went to collect it myself and was shown it working by the seller. It was demonstrated working but with the belt running in reverse and the seller suggested swapping the 2nd & 3rd phases to correct this as he had just done with a new machine replacing the one being sold.
When I got it back to my workshop I plugged it into my supply but nothing, not even in reverse. Swapped the 2nd & 3rd phases at the machine socket but still nothing.
I’ve looked for a micro switch on all openable areas but can’t find any. Seems unlikely that it’s broken on such a short journey. Am I missing something really obvious?
 
How is your own three phase provided? From the national grid or via a VFD/phase converter/magic box?

What make and model of machine? Have you looked for a manual?

Photograph the relevant parts or describe in detail the flow of electricity from the plug to the motor.

Verify with a voltage tester pen how far the electricity is reaching.
 
How is your own three phase provided? From the national grid or via a VFD/phase converter/magic box?

What make and model of machine? Have you looked for a manual?

Photograph the relevant parts or describe in detail the flow of electricity from the plug to the motor.

Verify with a voltage tester pen how far the electricity is reaching.
Power is by national grid directly. 16amp supply that usually powers my planer. 16 amp red plug that plugs directly into socket of machine. Power is there at the switch on the machine- didn’t test further yet.
The machine is similar to picture below.
Haven’t looked for a manual yet but will do.
Thanks.
 

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Swapping any two of the brown, black and grey wires (L1, L2, L3) will reverse the rotation of a 3 phase motor. There's nothing amiss about that.

In the terminal box of the motor, there will be two rows of three screw terminals.
You are connecting the machine to 415v 3 phase mains. That means your power cable inside the terminal box should go to 3 of these terminals all in the same row. The second row of 3 terminals should all be connected together by means of two brass or copper links. This is called star connected. Sometimes two links are doubled up, this is good and which side the double is on is unimportant.

When you saw it demonstrated, there is a small risk that the seller of the machine was powering it from a transwave, or other "phase converter" using 3 phase 240V not 415V that you get from the grid. If this was the case, the brass or copper links in the motor termi al box would be connecting the terminals in 3 pairs of two, like a short ladder. That is called delta connected. You must not connect a 240v delta wired motor onto 415v mains. You'll cook it. The motor needs to be changed to star connected first.

If all this is new to you I suggest you get help. 415v takes no prisoners if you make a mistake.
 
I like @ChaiLatte 's approach of thinking of the basic's first, it was seen working before being moved and now does not work following the move so E-Stop latched is a good start.

@petertheeater did you buy from just a seller such as ebay or a trade outlet, ie a workshop enviroment ?
 
Power is by national grid directly. 16amp supply that usually powers my planer. 16 amp red plug that plugs directly into socket of machine. Power is there at the switch on the machine- didn’t test further yet.
The machine is similar to picture below.
Haven’t looked for a manual yet but will do.
Thanks.
Sorry if I offend but, may I ask do you have a 3Phase supply at your address then, please?
 
Power is by national grid directly. 16amp supply that usually powers my planer. 16 amp red plug that plugs directly into socket of machine.
@DRC he does have a three phase supply unless someone has used the red three phase connectors instead of the blue 230 volt ones for a single phase supply but I would say he probably knows whether his existing planer is a single or three phase machine !
 
Swapping any two of the brown, black and grey wires (L1, L2, L3) will reverse the rotation of a 3 phase motor. There's nothing amiss about that.

In the terminal box of the motor, there will be two rows of three screw terminals.
You are connecting the machine to 415v 3 phase mains. That means your power cable inside the terminal box should go to 3 of these terminals all in the same row. The second row of 3 terminals should all be connected together by means of two brass or copper links. This is called star connected. Sometimes two links are doubled up, this is good and which side the double is on is unimportant.

When you saw it demonstrated, there is a small risk that the seller of the machine was powering it from a transwave, or other "phase converter" using 3 phase 240V not 415V that you get from the grid. If this was the case, the brass or copper links in the motor termi al box would be connecting the terminals in 3 pairs of two, like a short ladder. That is called delta connected. You must not connect a 240v delta wired motor onto 415v mains. You'll cook it. The motor needs to be changed to star connected first.

If all this is new to you I suggest you get help. 415v takes no prisoners if you make a mistake.
Hi. Yes the original was plugged into normal 3 phase
 
Hi. Yes the original was plugged into normal 3 phase
There is power to the switch and power to the connector. If I move the switch on the connector it powers the motor but I only tested that for a second. So either the connector is faulty or it is not opening the circuit due to a problem with the input. Could the connector have developed a fault? I can’t help but think this must be something straightforward and dare I say obvious that I am missing. I’ve spoken to the seller and he is genuinely surprised.
 
There is power to the switch and power to the connector. If I move the switch on the connector it powers the motor but I only tested that for a second. So either the connector is faulty or it is not opening the circuit due to a problem with the input. Could the connector have developed a fault? I can’t help but think this must be something straightforward and dare I say obvious that I am missing. I’ve spoken to the seller and he is genuinely surprised.
pictures
There is power to the switch and power to the connector. If I move the switch on the connector it powers the motor but I only tested that for a second. So either the connector is faulty or it is not opening the circuit due to a problem with the input. Could the connector have developed a fault? I can’t help but think this must be something straightforward and dare I say obvious that I am missing. I’ve spoken to the seller and he is genuinely surprised.
Pictures
 

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