Ok so I have read a lot that these damn volt and amp meters are a huge pain in the ass in these things and seem to be all that ever goes wrong and gives a lot of people issues. Me being one. I am not sure what's going on. When I use my multi meter to measure my current coming from my power supplies I'm showing 3.7volts. As soon as I plug the volt and amp meters in it drops to like .3 volts and the amp and volt meters won't show up. I can turn the set screw and eventually get the volt meter to show a faint number but it's showing 450-500 amps. Can't be right. Checked everything with my multi meter and showing 224 on my 220 circuits and 121.5 on my 120 circuits. Not to smart with electricity so scared to use my multi meter to check the 2 lines tied to the relay and main bus in the panel. Not sure if I can or I'll blow something up. Also not sure if I can use the amp meter to measure the amps across the shunt by simply touching both metal plates on it. Either way why would my volt and amp meters drop the supply voltage so much and not actually light up. To even get the volt meter to light up I have to turn the set screw a lot and then when I unplug the volt meter it's showing I'm supplying it with 9 volts. As the volt meter is 5 volt max I don't want to leave it there as I'm scared to burn it out however when it is plugged in it's only reading .9 volts on my multimeter. Anyone ever have this issue. I followed everything exactly as they showed on there website and I'm using the volt and amp meters they supply on there site.
Help with Electric Brewery control panel build
- Thread starter Izzie1701
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How about a circuit diagram so we have some idea of you you have everything connected.
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Dfitz
Well-Known Member
Two things, your power supply should be sending 5 volts to the meter. Try switching the wires (+/-) on your power supply.
It does supply this to the lines but then the lines drop as soon as the volt meter or amp meter are plugged in to nearly 0. When I test the polarity I have the ground and positive attached as per the above diagrams. The amp meter won't even light up at all.
Sorry it supplies just under 4. There instructions said to start lower then 4 and then turn it up slowly till the light brightness matched the brightness of the amp and volt meters. Only thing is I turn it and turn it and the D.C. Volts stay the same till I unplug them then they show 9. Would the polarity of the 2 cause this. I can try and swap them just it's currently wired with the positive to the positive as per the diagram.
We need more info to help you. First I would say would be to make sure models need 5VDC, not 12 or 24VDC.
I would isolate them from the rest of your circuitry. The ammeter should read zero connected to shunt with one end of shut disconnected so no current can flow through it. And the voltmeter should read the same voltage across its input terminals. Test one at a time. It is not likely that both are bad. Also check that your power supply works. Maybe plug a known device into its power like a tablet which draws an amp or two. The meters should draw very little so the voltage input to them shouldn't drop unless your supply is wonky.
I would isolate them from the rest of your circuitry. The ammeter should read zero connected to shunt with one end of shut disconnected so no current can flow through it. And the voltmeter should read the same voltage across its input terminals. Test one at a time. It is not likely that both are bad. Also check that your power supply works. Maybe plug a known device into its power like a tablet which draws an amp or two. The meters should draw very little so the voltage input to them shouldn't drop unless your supply is wonky.
augiedoggy
Well-Known Member
Im not sure why the ones used in the very old electric brewery build list are still so popular but there have been a lot of newer and easier to wire volt and amp meters that do so much more (Yes Brundog for less $$ too 
)
I currently use this one in my control panel and it works great. not only does it give me real time amp and volt reading but also wattage draw and a KWH meter that I can reset easily if I like
http://www.ebay.com/itm/100A-AC-Vol...251932?hash=item1c6e47515c:g:k04AAOSwFV9Xxp7V
It runs of any ac voltage from 80 to 280v ... cant get much simpler to wire up really.... The ac line clamp goes around the voltage line you want to measure amps/watts from... no shunts or external doorbell transformers needed.
color matching ones are also available for those who favor looks over function. http://www.ebay.com/itm/AC-80-300V-...0b4635c&pid=100005&rk=6&rkt=6&sd=122109251932
)I currently use this one in my control panel and it works great. not only does it give me real time amp and volt reading but also wattage draw and a KWH meter that I can reset easily if I like
http://www.ebay.com/itm/100A-AC-Vol...251932?hash=item1c6e47515c:g:k04AAOSwFV9Xxp7V
It runs of any ac voltage from 80 to 280v ... cant get much simpler to wire up really.... The ac line clamp goes around the voltage line you want to measure amps/watts from... no shunts or external doorbell transformers needed.
color matching ones are also available for those who favor looks over function. http://www.ebay.com/itm/AC-80-300V-...0b4635c&pid=100005&rk=6&rkt=6&sd=122109251932
Im not sure why the ones used in the very old electric brewery build list are still so popular but there have been a lot of newer and easier to wire volt and amp meters that do so much more (Yes Brundog for less $$ too
I currently use this one in my control panel and it works great. not only does it give me real time amp and volt reading but also wattage draw and a KWH meter that I can reset easily if I like
http://www.ebay.com/itm/100A-AC-Vol...251932?hash=item1c6e47515c:g:k04AAOSwFV9Xxp7V
It runs of any ac voltage from 80 to 280v ... cant get much simpler to wire up really.... The ac line clamp goes around the voltage line you want to measure amps/watts from... no shunts or external doorbell transformers needed.
color matching ones are also available for those who favor looks over function. http://www.ebay.com/itm/AC-80-300V-...0b4635c&pid=100005&rk=6&rkt=6&sd=122109251932
So I am assuming then I just clamp the clamp around the main line feeding the panel and run the 2 power supply lines back to my neutral and positive buses.
jeremy2027
Well-Known Member
Since you have two holes already you can go to Auberins.com and purchase their separate volt and amp meters. They connect the exact same way on a wide voltage scale so need for the whole doorbell converter setup. I have them in my electric panel and they are a far easier solution.
augiedoggy
Well-Known Member
exactly or power it with the 2 hot lines if its 240v.. either will work.... and you will have twice the functionality. the real time watt meter comes in handy to easily see what kind of power is being put out on your elements at any given time. the WH meter is cool to see how much electricity each brewing process uses and break down the cost if wanted...
augiedoggy
Well-Known Member
Lets be clear that those are just the $4 stripped down cheap meters like this http://www.ebay.com/itm/4-wire-Blue...440048?hash=item258b096a70:g:tMQAAMXQ1d1THscc marked up to be 2-3 times the normal retail and more than double the price with half the functionality of the single solution I already mentioned?. they are made with by the same company though it seems because I have both from some other projects. They are also not as easy to wire up as the meter I mentioned above... but if you want to go that way It your choice of course and you can do it for $9 total vs 25-$35 + shipping from auber for the exact same thing, again your choice Im just pointing it out...
I would just leave the the old volt meter in place and not power it up.. problem solved. save it for future use.
I agree with doggie on this one. These meters are cheap and all made by one company.
That said, you should be able to get the ones you have working for zero dollars. The fact that NEITHER works right is a red flag that it is not the meters. To prove, test them separately with a different power source. If your supply is a decent regulated or switching supply (which you should confirm) there should be no voltage drop once powered up. Each meter should only draw a few mA... less than a phone charging.
That said, you should be able to get the ones you have working for zero dollars. The fact that NEITHER works right is a red flag that it is not the meters. To prove, test them separately with a different power source. If your supply is a decent regulated or switching supply (which you should confirm) there should be no voltage drop once powered up. Each meter should only draw a few mA... less than a phone charging.
If you see 3.7V out of the DC regulator that feeds the panel meters then the voltage drops to almost nothing when the panel meter is connected this sounds like you may have the + and - reversed. It is not uncommon for devices to have a diode on the input for reverse polarity protection which would cause the voltage to drop down to a few tenths of a volt. If there is no input protection and you did have the polarity reverse at some point it is possible that the meter is fried and could give a similar results.
I agree with Brundog in that is might be possible to use what you already have. I would remove the panel meters and connect up just the input power connections to a 5V phone charger/wall regulator to see if they power up. You need to make sure the phone charger has an appropriate output current for the meter. If the meters light up the issue is most likely the DC regulator and/or wiring.
You can also check the DC regulator with a different load, maybe a small 5V fan to see if that is working correctly. You want to put a load that is close to what the meter is suppose to be using.
augiedoggy
Well-Known Member
You should be able to test power it off of 4.5v from 3- 1.5v batteries as well... like from a battery pack out of a cheap harbor freight LED flashlight...
Tried this like doggie said with a remote control car power supply I had kicking around. 3 - AAA batteries. Still nothing. Checked batteries with volt meter to make sure they were not dead. Not dead. Looks like o have faulty amp and volt meters. Canada post did look to have used and abused them in shipping. The package was also shoved into a little PO box so I'm sure all the miss handling would have mangled these up pretty good. Either way i purchased the $14 volt/amp meter doggie suggested. Like that I can get rid of the heavy doorbell transformers and actually return them and get money back ($25 each) so I'm actually saving some money this way as well. Not much but will buy me a few hops.
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