Can Ammeter damage Power Supply?

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • caspian
    Badcaps Legend
    • Oct 2015
    • 1589
    • Laptop

    #1

    Can Ammeter damage Power Supply?

    Dear Members,

    My DC linear Lab Power Supply does not display the current and voltage correctly. Thus, I am going to connect an Ammeter/Voltmeter Module to the DC output of the power supply. Then, a load will be connected the takes about 1-5volts with 0.1-1.5Amps.
    But I heard If I connect an Ammeter to the output of the power supply, then the Ammeter module is not isolated from the power supply so that the Ammeter can damage the power supply.
    Is this true?

    Thanks

    I have attached the photo of a sample Ammeter module that I am going to buy. I have attached a photo of my power supply too.
    Power Supply: 15v 2A Variable Linear DC
    Ammeter/Voltmeter: 100v 10A DC
    Attached Files
    Last edited by caspian; 06-05-2022, 02:33 AM.
  • RukyCon
    A Fake Rubycon
    • Jan 2017
    • 816
    • USA

    #2
    Re: Can Ammeter damage Power Supply?

    I've used those displays before, and they do not have to run on a isolated supply, in fact, the ground wire for the display power is commoned to the current shunt ground, so if you do try to use an isolated supply, then both supplies will end up having a common ground, thus end up not being isolated. Some listings for these will also show them getting powered by the same supply they're reading from (attached below is one such image i found).
    Attached Files
    I'm not a expert, I'm just doing my best.

    Comment

    • stj
      Great Sage 齊天大聖
      • Dec 2009
      • 30952
      • Albion

      #3
      Re: Can Ammeter damage Power Supply?

      you cant read voltages below the operating threshold like that,
      the meter power will have to be tapped from some other place in the psu

      Comment

      • caspian
        Badcaps Legend
        • Oct 2015
        • 1589
        • Laptop

        #4
        Re: Can Ammeter damage Power Supply?

        I am going to provide a separate power to the Ammeter/Voltmeter module from an AC power adapter. (see the picture)
        The power adapter is completely separate from the linear power supply, except for their ground.
        I want the Ammeter/Voltmeter module to be able to measure all voltages from 0v to 15v and all currents from 0A to 5A, specifically the values near 0.
        Now I have got a question:
        What voltage and current should the power adapter provide for the Ammeter/Voltmeter module so that the Ammeter/Voltmeter module be able to measure all voltages from 0v to 15v and all currents from 0A to 5A?
        Attached Files
        Last edited by caspian; 06-16-2022, 07:16 AM.

        Comment

        • sam_sam_sam
          Badcaps Legend
          • Jul 2011
          • 6027
          • USA

          #5
          Re: Can Ammeter damage Power Supply?

          This depends on the meter module to what voltage it will work at
          Now some meter modules can be modified to work on a separate power supply I have done this personally before but not all can be done easily the smaller the meter module the harder this procedure is to be done

          Now some have it where the voltage meter inputs are isolated but not the current sensing especially if it has the dual display

          If you want to have a isolated current module you need to get a meter module that has a 5 input and states that it is isolated however if go this route the shunt has specifications like 75 mil volts for a 100 amp shunt and you would have to a scale for what each mil volt means for amp of current

          Now there is another option for dc voltage/current and it is a external amp current pickup sensor
          I would caution you that if you go this route the quality of these units are not always good what I mean is that sometimes the actual current draw is not what is displayed some of them you adjust the meter for accuracy but be aware not all of them have this option —> this is extremely hard to find

          This meter module might be what you are looking for

          https://www.ebay.com/itm/27486669262...id=23033951229

          This shows you how to hook up the the meter module

          https://i.ebayimg.com/images/g/Gq8AA...TQ/s-l1600.jpg

          One note the minimum voltage for this setup is 8 volts to a maximum of 12 volts

          This type of meter module is hard to find

          I have not personally use this exact module before I found this type when looking for the other type that I mentioned earlier but I am going to buy a couple of them and try them
          Last edited by sam_sam_sam; 06-19-2022, 04:34 AM.

          Comment

          Related Topics

          Collapse

          • Tynan Dill
            Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?
            by Tynan Dill
            I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.

            Upon bringing it home and plugging it up, it showed a standby light.

            I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.

            The screen seems to blackout and stay black, but with a flashlight I can see the display.

            With my Playstation 4 connected via HDMI, and running a game I can hear sound.

            Assuming...
            11-22-2024, 01:46 PM
          • sam_sam_sam
            Desoldering gun station modified to use a 18 volt @ 20 amp switching power supply
            by sam_sam_sam
            I have wanting to do this project for quite sometime now and I finally found a switching power supply that will work on this desoldering gun station ZD-915 that the original switching power supply took a shit and just was not worth trying to fix it because this switching power is not quite big enough to handle the heater element and the vacuum pump

            One note when I tested the switching power supply and the voltage control board I noticed that this desoldering gun heat up much faster than the original switching power supply which I was really surprised by to the point that I might buy...
            03-31-2024, 02:12 PM
          • sam_sam_sam
            Modification to a ZD-987 desoldering/soldering station using a external switching power supply
            by sam_sam_sam
            I have been working on this concept for quite some time now with limited success but recently I found a switching power supply that is setup for the voltage that this soldering station needs to operate at however it also needs part of the secondary circuit from the original switching power because you need several voltage rails

            I once tried to get a ZD-915 desoldering station to work on a 18 volt battery power supply but unfortunately things did not go well but I did find a work around but I might try this idea again but going at a little differently more about this another time...
            07-01-2024, 06:34 AM
          • JimBanville
            Definitive technology SC 2000 subwoofer amp's power supply clicking and popping
            by JimBanville
            The sub developed a constant popping every couple seconds from woofer and power LED flickering with nothing but wall AC connected. Connecting an audio cable didn't change anything. It doesn't play but a second or two of audio in between the pops.
            Opened it up and discovered the power supply is making a faint clicking or ticking sound.
            I measured the amp's output to the woofer and it pulses up to 50mv DC to be driver. The pulses coincide with the power supply ticking/clicking.
            I measured the power supply output going to the amp board and it too has this pulsing. Voltage cycles...
            09-13-2023, 07:21 AM
          • CMCM
            Russound CA4 Power Supply Repair
            by CMCM
            Hello Everybody,

            Trying to repair a power supply from a Russound CA4 Multizone Controller (picture attached)

            Russound no longer supports it but were kind enough to provide a schematic of the power supply (pdf attached).

            The outputs marked 12v and 20v are all measuring only 1v.

            The board is clicking, which I think means it is in something called hiccup mode when the flyback transformers switches because of an internal problem or something else on the board Overloading it.

            The capacitors physically look clean (no bludgesor leaks) and...
            07-03-2025, 01:12 PM
          • Loading...
          • No more items.
          Working...