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Onoff
In the land of the unfinished project I am King!
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Having made a bit of bench space I just had a play with reconfiguring this 5kVA site transformer.
I've "stacked" the primary winding on top of the secondary as per the sketch below.
First I disconnected the wires to the 110V sockets and clipped them out of the way.
Then I put a 3-way Wago in where the incoming L goes to the primary.
I then cut the incoming earth that goes to the centre tap on the secondary and isolated both ends with Wagos.
I cut the incoming neutral where it goes to the primary and put in another 3-way Wago. To this I connected the L of the secondary.
My new "take off" is then from the original L on the primary and N of the secondary.
Getting 330VAC. I must check the volt drop out to the garage.
What else.....I'd take the incoming earth to any circuit I connect but leave the centre tap earth isolated.
Need to clear some more bench space now to get the motors on there!
I've "stacked" the primary winding on top of the secondary as per the sketch below.
First I disconnected the wires to the 110V sockets and clipped them out of the way.
Then I put a 3-way Wago in where the incoming L goes to the primary.
I then cut the incoming earth that goes to the centre tap on the secondary and isolated both ends with Wagos.
I cut the incoming neutral where it goes to the primary and put in another 3-way Wago. To this I connected the L of the secondary.
My new "take off" is then from the original L on the primary and N of the secondary.
Getting 330VAC. I must check the volt drop out to the garage.
What else.....I'd take the incoming earth to any circuit I connect but leave the centre tap earth isolated.
Need to clear some more bench space now to get the motors on there!
whats bench space??
Onoff
In the land of the unfinished project I am King!
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A mythical beast like "garage floor" and "clear working area". It's nemesis being "stuff I can't say no to" and "that's too good to go in the skip".
Onoff
In the land of the unfinished project I am King!
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- Location
- Sevenoaks, UK
Happiness is a bit more space, the radio on, the gentle hum of a fan heater, having the right bits to hand, namely some ancient H07RNF and even the correct PG16 glands for the Italian motor...and a beer (albeit in the wrong glass):
L1 & L3 will come from the autotransformer. LA is the "artificial" phase.
I'm even being extra tidy and having a bin:
I just want my blingy, Chinesium meters to turn up now!
L1 & L3 will come from the autotransformer. LA is the "artificial" phase.
I'm even being extra tidy and having a bin:
I just want my blingy, Chinesium meters to turn up now!
Glad you underdstand it all . Lol
Onoff
In the land of the unfinished project I am King!
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Hmmm.....at the mo this converter of mine works as aforementioned; hold down the spring loaded SW2 (bringing the 75uF start cap in) then switch on SW1, the big red switch. As soon as the motor is up to speed release SW2.
I'm wondering if a tachometer relay would would to be able to ditch SW2?
Or add a 1500rpm centrifugal switch to BOTH motors, wired in series.....
I'm wondering if a tachometer relay would would to be able to ditch SW2?
Or add a 1500rpm centrifugal switch to BOTH motors, wired in series.....
Pete.
Member
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If SW1 was a relay and SW2 activated a timer relay you could use SW2 to activate the timer relay which then invoked relay SW1, which is self-latching. When the timer relay drops out it disconnects the start cap.
Even better use one of my sprung-one-way 3 position switches and it will work like a car ignition switch. Off, on and start.
Even better use one of my sprung-one-way 3 position switches and it will work like a car ignition switch. Off, on and start.
Onoff
In the land of the unfinished project I am King!
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I was only thinking tacho relay as I thought I had a Tempatron one somewhere...can't find it.
Going to brave the garage in a mo as I'm sure I've an "ordinary" DIN mounting timer I saw the other day mid sort out.
Might take you up on a switch depending on what I've got here myself.
Or I may just sit here in the warm with my Theakstons Old Peculier, it's bloody freezing down here, first frost on the car this morning. Just been out cutting MDF and it's brass monkeys!
Hopefuldave
Intergalactic pot-mender
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I set mine up with a dual-pole relay feeding the main motor and start contactors' coils, only the motor contactor is held on by its aux contacts, so I just hold the start button down until the motor's spinning, then it runs after I let go.
Dave H. (the other one)
Dave H. (the other one)
What I had with my old rotary, was a 240VAC relay between the idler star point and the false phase, so once the motor got up to speed, the start capacitors dropped out.
The only issue I had, was if you started a big load, the relay would chatter until the load got up to speed. If I was to build another rotary, I'd have a 240VAC trigger a short time delay relay, so things didn't chatter as much.
The only issue I had, was if you started a big load, the relay would chatter until the load got up to speed. If I was to build another rotary, I'd have a 240VAC trigger a short time delay relay, so things didn't chatter as much.
Onoff
In the land of the unfinished project I am King!
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Wow! Was it really that long since I was playing with this and had a clear bench?
Anyway...
I've rewired a 110V site transformer as above to give nom 230 + 110 so circa 340V as one of my phases.
This large trannie I've got, been trying to think of a use for it. It'd give me 230+190 so 420V:
Thinking though the 5kVA 110 trannie might be better than this 1.8kVA one?
Anyway...
I've rewired a 110V site transformer as above to give nom 230 + 110 so circa 340V as one of my phases.
This large trannie I've got, been trying to think of a use for it. It'd give me 230+190 so 420V:
Thinking though the 5kVA 110 trannie might be better than this 1.8kVA one?
Memmeddu
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Bigger one will manage the heat better
I've found myself in need to build an RPC after my latest acquisition.
Today I've bought a cold saw, it has a 2 speeds motor which can't run without three phase.
Now if once opened I discover it can be saved, it would be very likely that the windings layout doesn't allow me to use 230V
selectedgrub
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Is this for the cat's tree house?
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,801
- Location
- Sevenoaks, UK
Close. About 10' away in fact.
Onoff
In the land of the unfinished project I am King!
- Messages
- 12,801
- Location
- Sevenoaks, UK
Bump! Anyone ref my above post? If I reconfigure this 230 / 190 V trannie as an autotransformer I should get 420V?
