Drok Hall Effect DC power monitor ?'s

[SCClockDr]

I've been fiddling with 2 Drok Hall Effect DC power monitors.​

1. DROK DC 0-300V 200A STN LCD Display Digital Multimeter (01)
2. DROK DC Voltmeter Ammeter, 0-90V 100A Digital Voltage Current Capacity AH WH Power Time Multimeter (02)

Here are a few of the things I've discovered along the way.
Meter 01

Retains the cumulative Data regardless of power interruptions.​

Will track negative results to the maximum digital capacity of the display.​

The meter will display current with the current wire passing through the coil in either direction.​

Back light needs to be manually controlled.​

Is capable of using battery voltage for power while monitoring a different voltage that corresponds with the amperage being recorded.​

Does NOT have a clock display.​

Meter 02

Retains the cumulative Data regardless of power interruptions.​

Will NOT track negative results below zero, it will count down a positive result till it reaches zero though.​

The meter will NOT display current with the current wire passing through the coil in a direction resulting in negative result.​

Back light internally controlled. Edit: Back light can be forced on/off as well.​

Is capable of using battery voltage for power while monitoring a different voltage that corresponds with the amperage being recorded.​

Does have a clock display that reflects the duration of the sampling period.​

So based on these findings meter 01 seems best suited to monitor battery current & is equally suited to monitor other currents provided no clock data is needed. Meter 02 is best suited for monitoring unidirectional currents like PV, SCC out, battery charger, or Load. The image shows the sources that are needed to operate meter 02 sampling a different voltage from its power source.

 

[SCClockDr]

If anyone has sources for competing hall effect monitors I'm definitely interested.
Any corrections, additional info, or operational guidance is also welcomed.

 

[SolarRat]

I bought a very similar meter (same housing) but with the 100amp shunt. It worked great on my boat...for a total of 31 days before it croaked. It was in a dry location but the Florida heat/humidity probably killed it. Just a word of warning, these things need to be kept indoors. I'm now searching for something a little more robust (but still affordable).

 

[SCClockDr]

I bought a very similar meter (same housing) but with the 100amp shunt. It worked great on my boat...for a total of 31 days before it croaked. It was in a dry location but the Florida heat/humidity probably killed it. Just a word of warning, these things need to be kept indoors. I'm now searching for something a little more robust (but still affordable).

Meters will be inside the trailer, the coils will be enclosed but not inside the living space. I've used an AC version of theirs for several years no issues.

 

[SCClockDr]

Update:
Meter # 2 the one pictured seems to be having issues. It refused to register any current after it auto screen offed. I opened the PV circuit and reset the current value to zero. Closed the PV circuit and it refused to see any current. I mucked around a bit and when the pointer re-entered the bottom of the screen it started to register current again. Then it briefly went dark, re-lit showing zero current.
I would class this unit as unreliable ATM.

 

[offgriddle]

I've been fiddling with 2 Drok Hall Effect DC power monitors.​

1. DROK DC 0-300V 200A STN LCD Display Digital Multimeter (01)
2. DROK DC Voltmeter Ammeter, 0-90V 100A Digital Voltage Current Capacity AH WH Power Time Multimeter (02)

Here are a few of the things I've discovered along the way.
Meter 01

Retains the cumulative Data regardless of power interruptions.​

Will track negative results to the maximum digital capacity of the display.​

The meter will display current with the current wire passing through the coil in either direction.​

Back light needs to be manually controlled.​

Is capable of using battery voltage for power while monitoring a different voltage that corresponds with the amperage being recorded.​

Does NOT have a clock display.​

Meter 02

Retains the cumulative Data regardless of power interruptions.​

Will NOT track negative results below zero, it will count down a positive result till it reaches zero though.​

The meter will NOT display current with the current wire passing through the coil in a direction resulting in negative result.​

Back light internally controlled. Edit: Back light can be forced on/off as well.​

Is capable of using battery voltage for power while monitoring a different voltage that corresponds with the amperage being recorded.​

Does have a clock display that reflects the duration of the sampling period.​

So based on these findings meter 01 seems best suited to monitor battery current & is equally suited to monitor other currents provided no clock data is needed. Meter 02 is best suited for monitoring unidirectional currents like PV, SCC out, battery charger, or Load. The image shows the sources that are needed to operate meter 02 sampling a different voltage from its power source.

Meters are essential tools to monitor, understand, troubleshooter, maintain and improve our power systems. I noticed that the meters selected operate on the Hall Effect principle. I had a Ford Bronco in the 80's that had a Hall Effect transducer in the distributor. Here is a explanation of the Hall Effect:

 

[stu]

This guy likes this unit, he explains the difference between the two units

 

[Sanwizard]

I just purchased two of the number 1's. 300v 200amp. I am hoping to be able to use these to display at a glance PV power to my inverters. I am amazed that the little rectangle MC4 inline meters max out at 60V. Not good for a PV string at 250V.
Those little beasts are perfect doe a single panel. Does anyone know why there seems to be nothing on the market for monitoring DC PV string power? I know my inverter can display it, but having a simple always on digital display would be very helpful to troubleshoot.

 

[Bud Martin]

300 Volt, 100 Amp Meter for Solar Panel​

 

[Sanwizard]

Thanks Bud! That little device looks perfect!

 

[Sanwizard]

300 Volt, 100 Amp Meter for Solar Panel​

Sold out. Figures!

 

[Bud Martin]

This one should work also. I am still searching for that board version on Ali but they do not make that version any more, I bought two from the store in the link below for $12 ea after seeing it on one of Will's video and I really like it and I'm trying to get more of that form factor .

13.97US $ 35% OFF|DC digital voltmeter 300V/100A ammeter voltage Mobile APP meter car battery capacity volt current detector power supply tester|Voltage Meters| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

 

[Sanwizard]

Came to a bit over $15 with tax. Thanks!

 

[markb]

I have meter #2 above. I've had it a while, and it's showing current and voltage correctly. But it always shows the battery SOC as 100%. How do I get this to work? Any hints?

 

[markb]

I have meter #2 above. I've had it a while, and it's showing current and voltage correctly. But it always shows the battery SOC as 100%. How do I get this to work? Any hints?

Replying to myself, here, in case anyone comes across this post with the same question.

So the way this works is:

1) You need to set a reasonable amp-hour value for OAH. This is is used the the percent calculation. You can dial in a more exact value later.

2) Either charge the battery to what you want to be 100%, or discharge to what you want to be 0%.

3) Now reset the SoC of the meter by pressing the down arrow to move the pointer the last option (LOP), and then press it again. The arrow should disappear. Now press OK to reset the SoC. You can press OK again to toggle between 0% or 100%, whichever matches the actual state of charge.

4) Now the SoC meter should work approximately. To dial in a more accurate OAH, You can use the meter to do capacity test. For instance, from a full charge, note the AH value at the bottom of the screen. Discharge to the appropriate cutoff point, and note the new AH value. The difference is the battery capacity. Enter that value for OAH.

 

[Sanwizard]

Replying to myself, here, in case anyone comes across this post with the same question.

So the way this works is:

1) You need to set a reasonable amp-hour value for OAH. This is is used the the percent calculation. You can dial in a more exact value later.

2) Either charge the battery to what you want to be 100%, or discharge to what you want to be 0%.

3) Now reset the SoC of the meter by pressing the down arrow to move the pointer the last option (LOP), and then press it again. The arrow should disappear. Now press OK to reset the SoC. You can press OK again to toggle between 0% or 100%, whichever matches the actual state of charge.

4) Now the SoC meter should work approximately. To dial in a more accurate OAH, You can use the meter to do capacity test. For instance, from a full charge, note the AH value at the bottom of the screen. Discharge to the appropriate cutoff point, and note the new AH value. The difference is the battery capacity. Enter that value for OAH.

I have two of them, and they sort of work. I also have two Aili shunts with monitors. One works pretty good, but the other looses SOC after a day or so. My Victron shunt has been working perfect from day one, and is now integrated with my Pi4 and Solar-Assistant.IO software providing realtime status from anywhere. It keeps track of SOC perfectly.
You get what you pay for I guess.