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Old 05-12-2018, 07:47 PM   #1
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Name: Olivier
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Digital multimeter wrong current reading

Hey guys, I created a wiring PDF because I figured it would be easier to have help. You can find it here:
https://www.dropbox.com/s/ud5wjbiabu...ic_02.pdf?dl=0

So, here are my questions:

I just added a shunt + digital multimeter (link) on my Trillium 74. I wanted to see exactly the consumption of each things in my trillium. I'm learning a lot right now and might have done something wrong. I got 2 problems at the moment.

1) Recently, I installed an electric pump + faucet with switch. When I tested it prior to installing it the Trillium, the current was 1.7A (witch is what it should be).

Once installed in the Trillium, it says 3.5A on the digital multimeter (other reading seems right since it says 12.7V for the battery that was full). When I saw this, I tested again with my regular multimeter by placing it in the circuit between the slow blow fuse and the fuse block. It was still reading 1.7A like it was prior to installation. Any idea why I get 2 different reading?


2) My second problem is that when I turned on my faucet, the propane detector started to blink red and green (they are NOT on the same wiring as you can see in my wiring scheme). In the manual it says that I need to call the company when having this issue (on the forum I read that it might do this when the battery voltage is too low but its full). It wont come back to normal even after plug-unplug.

Thanks for your input!
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Old 05-12-2018, 08:30 PM   #2
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Quote:
Originally Posted by wysiwyg View Post
Hey guys, I created a wiring PDF because I figured it would be easier to have help. You can find it here:
https://www.dropbox.com/s/ud5wjbiabu...ic_02.pdf?dl=0

So, here are my questions:

I just added a shunt + digital multimeter (link) on my Trillium 74. I wanted to see exactly the consumption of each things in my trillium. I'm learning a lot right now and might have done something wrong. I got 2 problems at the moment.

1) Recently, I installed an electric pump + faucet with switch. When I tested it prior to installing it the Trillium, the current was 1.7A (witch is what it should be).

Once installed in the Trillium, it says 3.5A on the digital multimeter (other reading seems right since it says 12.7V for the battery that was full). When I saw this, I tested again with my regular multimeter by placing it in the circuit between the slow blow fuse and the fuse block. It was still reading 1.7A like it was prior to installation. Any idea why I get 2 different reading?


2) My second problem is that when I turned on my faucet, the propane detector started to blink red and green (they are NOT on the same wiring as you can see in my wiring scheme). In the manual it says that I need to call the company when having this issue (on the forum I read that it might do this when the battery voltage is too low but its full). It wont come back to normal even after plug-unplug.

Thanks for your input!
As to problem #1, per you diagram (and as it should be) your digital multi-meter is reading the combined current draws of all accessory's that are in use at any given time. It appears that the propane detector and the USB port are constantly drawing current therefore they would contribute to the overall reading of 3.5 amps. Although your diagram does not show it, I assume there is a switch in the circuit going to the ceiling lights. When in use, of course, they would add to the overall amp draw.

As to problem #2, I can offer no insight, but it appears from your manual that this is a known problem and perhaps the company can offer a solution.
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Old 05-12-2018, 08:38 PM   #3
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Name: Olivier
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Hi,

I didn't specify it in my previous message but , for problem 1, before turning on the switch for the faucet, the current read was 0A on the digital multimeter.

Only my waterpump and digital multimeter were connected since I removed all other fuses (lights, USB ) prior to testing.

Although, when problem 2 occured, everything was fused and connected properly. Every elements are on their own wire.

Also you are right, In my wiring diagram, I need to add a switch for the ceiling light and a switch for the USB since I have those in my setup.

Thanks for checking and for your input!
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Old 05-12-2018, 08:44 PM   #4
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Quote:
Originally Posted by wysiwyg View Post
Hey guys, I created a wiring PDF because I figured it would be easier to have help. You can find it here:
https://www.dropbox.com/s/ud5wjbiabu...ic_02.pdf?dl=0

So, here are my questions:

I just added a shunt + digital multimeter (link) on my Trillium 74. I wanted to see exactly the consumption of each things in my trillium. I'm learning a lot right now and might have done something wrong. I got 2 problems at the moment.

1) Recently, I installed an electric pump + faucet with switch. When I tested it prior to installing it the Trillium, the current was 1.7A (witch is what it should be).

Once installed in the Trillium, it says 3.5A on the digital multimeter (other reading seems right since it says 12.7V for the battery that was full). When I saw this, I tested again with my regular multimeter by placing it in the circuit between the slow blow fuse and the fuse block. It was still reading 1.7A like it was prior to installation. Any idea why I get 2 different reading?


2) My second problem is that when I turned on my faucet, the propane detector started to blink red and green (they are NOT on the same wiring as you can see in my wiring scheme). In the manual it says that I need to call the company when having this issue (on the forum I read that it might do this when the battery voltage is too low but its full). It wont come back to normal even after plug-unplug.

Thanks for your input!
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Old 05-13-2018, 07:21 AM   #5
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Olivier, You didn't state it in your post, but does the system have water in it. You tested it before installation (no load), now you test it in the system and if there is water in the system, then the pump will be under load and have a greater current draw. Could this be the case?
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Old 05-13-2018, 07:29 AM   #6
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Name: Olivier
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Hi! Yes I installed the tank, battery and pump in my kitchen prior to final installation for testing purposes. Water was flowing. It was reading 1.7A with my regular mutimeter. Thanks!
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Old 05-13-2018, 07:38 AM   #7
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The only thing I can think of is different pump loading. Perhaps longer lines, filters in the line, or other restrictions.
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Old 05-13-2018, 07:41 AM   #8
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The weird thing is that I get a different reading from my regular multimeter than the installed digital multimeter even if I only connect the pump
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Old 05-13-2018, 07:43 AM   #9
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Did you try removing the wired in multimeter and placing your portable multimeter in the same position?
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Old 05-13-2018, 07:46 AM   #10
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John, If you connect the two ammeters in series they should read the same.



Olivier, Do you have a third ammeter you can test it with?
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Old 05-13-2018, 08:08 AM   #11
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Thanks for your help guys.

No, I dont have a 3rd multimetre. I could borrow one though.

New information regarding problem 2. I just connected my battery to the smart charger. It said LOW. Then, while connected, I tested directly the propane detector on it and no more error signal. I dont understand why it said LOW since both multimeter was reading 12.7V off the charger.
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Old 05-13-2018, 08:34 AM   #12
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The pump might draw 1.7 A with free flow, but when it builds up pressure, the load will increase until the pressure switch turns the pump off. Just a thought.
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Old 05-13-2018, 09:07 AM   #13
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Maybe Paul... bu I still got 2 different readings. So you guys didnt see any issue the way I connected the shunt and the digital multimeter? I thought that could be the issue at first.
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Old 05-13-2018, 09:32 AM   #14
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Have you tried taking the positive lead loose from the fuse block hook it up separately to each item to see what your readings are?
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Old 05-13-2018, 09:53 AM   #15
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Have you tried taking the positive lead loose from the fuse block hook it up separately to each item to see what your readings are?
No I didnt. This way I can bypass the fuseblock? I can try that.. althought I need to connect at least the multimetre and the water pump to get a reading. Thanks
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Old 05-13-2018, 10:00 AM   #16
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Olivier, it may be that the electric pump is introducing electronic interference or high frequency fluctuations onto the wiring system. Sensitive sensors such as the ammeter and propane detector could be affected by such effects. Since it only occurs when the pump is running it should be an acceptable imperfection.
Have a good day,
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Old 05-13-2018, 11:12 AM   #17
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Battery Voltage

A fully charged 12V battery is 13.2 volts and a smart charger will most likely take the voltage to 14.2 before going into float mode.
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Old 05-13-2018, 12:06 PM   #18
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Anyone can point me to a trustable voltage chart fort a deepcycle 12v battery? Because dome charts state that 12.7 is good. Thanks!
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Old 05-13-2018, 01:32 PM   #19
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Originally Posted by J Ron View Post
A fully charged 12V battery is 13.2 volts and a smart charger will most likely take the voltage to 14.2 before going into float mode.
A fully charged battery is at 12.7 V. The proper way to measure is with all charging sources removed. If you have solar, wait until after dark. Give the battery a couple of hours after removing the charging sources for the surface charge to dissipate, or load the battery with a couple of amps for a half hour or so. The measurement should be made with no or minimal load on the battery.

The higher voltages measurements are only valid if the converter or solar controller is active, and do not indicate the actual state of charge of the battery. While many converter & solar controllers have adjustable voltages to match the battery type, 13.2 V is typical for the float stage of most charging devices, 14.2 V typical for the absorption stage, and 14.4 - 14.6 V typical for the boost or bulk stage.
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Old 05-14-2018, 05:18 AM   #20
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Olivier, I have another thought on the ammeter difference. If you have incandescent lights, turn off the pump and just turn a bunch of lights and check the two meters. If the readings are different you definitely have a calibration issue. If they are the same, the pump may, as suggested previously, be creating interference. Because incandescent lights are purely resistive loads, they will not produce any interference or noise. LED lights may contain switching regulators in them which can create noise.
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