24V to 5V step down

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Brewn4life

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Ok so I got my 24V AC/DC transformer for my gas valves and would like to use it for my SSR's (pumps) as well for the manual turn on. I'm going to run the 5Vdc from BCS for the auto turn on.(using a three way switch). Problem I am having is the only step down I can find I have to get from Hong Kong. I know some one hear has a good place to shop for this. What are you guys using Im thinking about 100W so if need be I can add to system.
Thanks,
Ryan
 
24Vdc to 5Vdc, but Im thinking the SSR's have a 3-32Vdc trigger any ways.
https://www.oscsys.com/store/product/272
So what the hell I could just get a 3 way switch that can handle 24Vdc which would be my manual on(pump) and BCS could handle the auto on/off. One transformer powering the pumps and gas valves. All different relays of course.

Oh and I have the transformer to go from 120Vac to 24Vdc
 
Actually upon further evaluation my transformer is actually a 110Vac to 24Vac...back to square one.....finding a control voltage source for the manual on of the SSR's
 
Put the 24VAC through bridge rectifier then connect the output through a big capacitor (like 1000 uF / 50V) to ground. The output will be about 30VDC which should be OK for the SSR input.
 
Put the 24VAC through bridge rectifier then connect the output through a big capacitor (like 1000 uF / 50V) to ground. The output will be about 30VDC which should be OK for the SSR input.

Actually, an unloaded 24VAC transformer will probably get you 28VAC, and rectified / filtered will end up 38-39 VDC. Depends on the current rating of the transformer.
 
Cool was looking at the Power supply's and that will work. All the Doorbell power supply's were AC out put so I m not sure which ones your talking about. Send a link please. I did not get a chance to look at the Bridge Rectifier yet will do after work. Thanks for your help.
 
Cool was looking at the Power supply's and that will work. All the Doorbell power supply's were AC out put so I m not sure which ones your talking about. Send a link please. I did not get a chance to look at the Bridge Rectifier yet will do after work. Thanks for your help.

Many of the wallwarts that you have for old appliances have a stepdown transformer, diode rectifier (half or full), and capacitive filtering already in the "wart". No point building your own.
 
Yup, Doesn't everyone have a junk box with at least a half-dozen various old wall warts in it?
 
Or just get a SSR that uses 24VAC control like the Crydom A2450E.

You may have to pay retail for one of those, I haven't seen any cheap knock offs.
 
Buthcher a wall wart and get to cookin a batch. You can get a wal wart at any flea mkt for a couple of bucks and be brewing in a few minutes. I have a 24 VDC and a 5 VDc transformer and regulated power supply in my controller and got both off of ebay from the US for about 15 bucks a poece. They are chinese but I have an american warranty if I have an issue or failure. Your second idea was even better, just use the 24 VDC to run the SSR's and the controller for the on off function. Less parts= less chance of wiring errors or releasing the magic smoke.
Wheelchair Bob
 
Got two wall warts and going to check for more. Does the current mater at all? Seems to me that it would take more then .6A.
 
The SSRs should take practically nothing. What else is it you're going to run? There's probably a rating on it somewhere.
 
Well I don't see any ampere rating, but like you said 20ma is all it takes for a good time. Cool I must have spent multiple hours trying to figure this out and viola there it is. lol Thank god it wasn't a snake.
Thanks again for all your help.
Ryan
 
Wall warts are simple and will do just fine. Looking for more power and voltage choices? Computer PSU. Grab one out of an old PC or salvage store, a switch, and a ceramic power resistor and you will have 5vdc and 12vdc all day long. Might also have 3vdc and some negative powers to make 8vdc and others odd one.
 
Thanks Jeepin, I got many wall warts and some lap top chargers as well. I take it you own a Jeep. I owned a 88 Wrangler and did a lot of wheelin. They're a lot of fun. I miss mine a lot.
 
Brewn4life said:
Thanks Jeepin, I got many wall warts and some lap top chargers as well. I take it you own a Jeep. I owned a 88 Wrangler and did a lot of wheelin. They're a lot of fun. I miss mine a lot.

Either will do fine. I'm talking about a desktop PSU though. Complete overkill for switching SSRs, but a worthwhile project if you need power later. Mine is a little 160W but that translates to 8.5A on the 5vdc and 12vdc lines. I am a Jeeper. I'm down to one, a 2004 WJ, but have had a few Cherokees and a Wrangler.

image-2541378893.jpg
 
Cool, Ill probably just use a wall wart call it done for the time being. We got a couple comp. at the house that are no good and will check out the power in them.
 
If your computer PSU isn't super old then it will be an ATX PSU. These will have either a 20 or 24 pin main power connector. By default only the 5v standby rail will be on. This is the purple wire I believe. If you connect a jumper wire from the green power enable wire to one of the black ground wires that will turn on the rest of the power rails. Yellow - 12v, red - 5v, orange - 3.3v. Some PSUs require a minimum load on some or all of the power rails for stable operation. We use 50 ohm resistors of the appropriate wattage to accomplish this at my work because we only pull off of the 12v rail.
 
crane said:
If your computer PSU isn't super old then it will be an ATX PSU. These will have either a 20 or 24 pin main power connector. By default only the 5v standby rail will be on. This is the purple wire I believe. If you connect a jumper wire from the green power enable wire to one of the black ground wires that will turn on the rest of the power rails. Yellow - 12v, red - 5v, orange - 3.3v. Some PSUs require a minimum load on some or all of the power rails for stable operation. We use 50 ohm resistors of the appropriate wattage to accomplish this at my work because we only pull off of the 12v rail.

I am fairly ignorant when it gets specific. Mine is an older unit with the 3/4 pin terminals. I am only using red, yellow, and black for 5 & 12 vdc. I did have to add a resistor and added in a switch and led for good measure. If I short it out and trip it I just have to flip a switch instead of unplugging it.
 
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