# 600 v dc to 24 v dc possible??

Discussion in 'The Projects Forum' started by semsemhts, Mar 17, 2014.

1. ### semsemhts Thread Starter New Member

Mar 17, 2014
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I am working in the field of electric railway
the overhead wire carrying 600 v dc
I want a circuit to convert 600 v dc to 24 v dc
by the way i am a mechanical engineer , mean i want some simple explanation
thanks,,

2. ### R!f@@ AAC Fanatic!

Apr 2, 2009
9,618
1,088

Welcome !

It is possible but I do not think we can't help you.

But I'd say this, you might need a very high power resistor. it depends on your current requirements.

3. ### AnalogKid AAC Fanatic!

Aug 1, 2013
5,644
1,594
Of course it's possible, it just depends on how much power you need and how badly you need it. For example, if you need 1 amp, you could get there with a 600 watt resistor; simple but impracticle. For any current over about 50 mA, or any isolation, you need a switching power supply. Although they are not as common as ones for more normal input voltages, I'm sure there are off the shelf units out there.

ak

Apr 5, 2008
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5. ### alfacliff Well-Known Member

Dec 13, 2013
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you stillhavnt said anuthing about how much current you need. a simple way to do it would be to get a 440 ac to 24 vdc switch mode power supply and feed it the 600 volts dc. the rectifiers will pass the dc and the supply will work the same as if it had 440 volts ac going in.

6. ### R!f@@ AAC Fanatic!

Apr 2, 2009
9,618
1,088
Really?

It's 600VDC u know

Jul 18, 2013
13,135
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Why not simply with a 600v/24v transformer?
Depending on what country you are in there are RR association regulations when operating into the control field.
In NA it is the AAR.
Max.

8. ### alfacliff Well-Known Member

Dec 13, 2013
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because simply, a 600 to 24 volt transformer would not work on dc without a chopper, or other wise converting the 600 volts dc to pulses or ac.

Jul 18, 2013
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I missed the 600vdc!
But even more I can see local Regs coming into it if there are any?
It was not stated if this is required on the Loco or at a stationary point?
Max.

10. ### Experimentonomen Member

Feb 16, 2011
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The only solution i see here in a DC/DC converter like the one berus posted.

11. ### quicksilver Member

Mar 6, 2008
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Do a search for "surplus sales of Nebraska". They may have what you need. Then download the PDF & do some research on the company (IF it's still in business) and show your supervisor. Check & see if it's acceptable. MANY items are made when the USA was a manufacturer (rather than after NAFTA passed) & therefore out of business. IF the materials have to be approved by certain safety organizations: you may be out of luck. But actually doing it (dropping it down) is not too tough, especially if the current is low. ceramic resistors & heavy bridge rectifiers are available from the above without paying big \$. The issues I would imagine are safety, safety, safety & approval rating from various oversight organizations.

12. ### Plasmahunt3r New Member

Feb 6, 2014
28
2
I had seen this circuit and I wanted to try it someday. It may suit your needs:

http://www.eleccircuit.com/the-variable-high-voltage-power-supply-0-300v/

You don't need the Transformer and the Bridge since you are already DC. You would need an appropriate 600v capacitor. You only need the components after the Bridge.

If you try it, post the results. I want to know if it works.

Apr 2, 2009
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14. ### Experimentonomen Member

Feb 16, 2011
331
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Linear regulators at these voltages ? Are you completely out of your mind ?

At these voltages, a switchmode DC/DC converter is the only possible solution, nothing else will work.

15. ### inwo Well-Known Member

Nov 7, 2013
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This mains supply will never use an isolation transformer on the input side.

16. ### semsemhts Thread Starter New Member

Mar 17, 2014
15
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first of all : thanks for reply R!f@@
the needed voltage about 28 volt dc & 60 Amp

thank u

17. ### semsemhts Thread Starter New Member

Mar 17, 2014
15
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wouldn't it burn
i am waiting for your replay
thanks

Mar 17, 2014
15
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19. ### semsemhts Thread Starter New Member

Mar 17, 2014
15
0
actually i searched in that company mentioned above but unfortunately i didn't find it
by the way the current required is 60 amp and voltage required is 28 volt
thanks a lot

20. ### semsemhts Thread Starter New Member

Mar 17, 2014
15
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the circuit mentioned to convert 220 v ac not 600 v dc , by the way the max. amp in this circuit is 100 mA.
but the required current 60 amp .