Cheap battery monitor instead of Victron BVM-702???

[RobFlynn]

I'm looking to order components for what initially will be a very basic battery + B2B battery charger setup with minimal electrics – just some LED lighting and a portable compressor fridge. I'm opting for a Victron 30A Non-Isolated DC-DC Charger and a Fogstar Drift battery, both with bluetooth and an apps, so I'll be able to monitor/set charging and monitor battery performance albeit a little clunky. I would like the convenience of monitoring the battery on a simple screen at a glance rather than be messing about with a phone and the Victron BVM-702 looks decent. It does feel like overkill though and a bit pricy, especially if/when I expand the system with solar and maybe introduce something like a GX Touch (It's my undersatnding that the BVM would become redundant?) Has anyone got any experience using a cheap shunt/display similar like this?

https://www.amazon.co.uk/YOJOCK-Battery-DC0-300V-Voltmeter-Multimeter/dp/B0BPY6L3HR

or this...

https://www.amazon.co.uk/Battery-Voltmeter-Ammeter-Voltage-Transformer/dp/B07D2X2JSH

I'd like to mount something with aon/off switch in the little cubby hole near the front overhead courtesy lights so cable lengths would be quite long in case that makes a difference!

Thanks

 

[roadtripper]

I don't have experience of either of those but if I was going to tinker with something cheap I'd be minded to use the one that used inductance rather than direct connection.

I'm not sure I'd trust a 300amp shunt that didn't have a brand name on with a reputation to protect.

 

[RobFlynn]

Very good perspective. Thank you.

 

[CJW]

The Renogy one is excellent and on offer at the moment on Amazon:

 

[Dellmassive]

The Renogy one is ok. A few members have it.

It doesn't meter very low power draws as good as the Victron.

The Victron smart shunt is excellent, and works with the App.

Or the Victron bmv712 has the added screen.

..

The Victron Orion has the app, but has very little monitoring features. You only see basic settings and voltage.

..

You can download the Victron app now and play with the demo files to see what the Smart bmv and the Orion looks like on the phone...

..

Below you can see the importance of a way of varifing the lifepo4 bms .

I'm currently correcting a 15% soc drift on my battery ..... 3% left to go.
....




....

 

[Bigsidavies]

The Renogy one is excellent and on offer at the moment on Amazon:

View attachment 214534

It’s £54.99 on the Renogy website and you can then use the 6% discount code too.

500A Battery Monitor with Shunt/Sampler (Coulomb meter)

Renogy 500A Battery Monitor is able to monitor the amperage flowing out of the battery bank and will give an accurate state of charge reading on the LCD screen.

uk.renogy.com

 

[CJW]

The Renogy one is ok. A few members have it.

It doesn't meter very low power draws as good as the Victron.

The Victron smart shunt is excellent, and works with the App.

Or the Victron bmv712 has the added screen.

..

The Victron Orion has the app, but has very little monitoring features. You only see basic settings and voltage.

..

You can download the Victron app now and play with the demo files to see what the Smart bmv and the Orion looks like on the phone...

..

Below you can see the importance of a way of varifing the lifepo4 bms .

I'm currently correcting a 15% soc drift on my battery ..... 3% left to go.
....

View attachment 214544View attachment 214545


....

Hi Lee. I checked my Renogy battery monitor by applying the smallest load I have - a 20ma night light LED. It picked it up accurately. The LED is just bigger than a pin head.

 

[Dellmassive]

Hi Lee. I checked my Renogy battery monitor by applying the smallest load I have - a 20ma night light LED. It picked it up accurately. The LED is just bigger than a pin head.

Awesome, any chance you can get a few pics of the screen?

Most shunts have issues below 500mA

the odd thing is they don't state the Amp range that the unit can detect the spec or manuals.

 

[RobFlynn]

I ordered the bmv712. I hadn’t realised it has a connection to expand the system out to a cervical via the monitor. Also has Bluetooth. I thought it was either BT or screen but bmv722 gas both. Spent so long pondering the battery sold out

 

[CJW]

Awesome, any chance you can get a few pics of the screen?

Most shunts have issues below 500mA

the odd thing is they don't state the Amp range that the unit can detect the spec or manuals.

Sure. First photo is at rest, the 40ma draw is from the monitors and the control panel.

Second photo is with ‘Nav Light’ on which is actually the tiny yellow LED.

Third is the tiny LED.

 

[roadtripper]

That's a really neat nightlight

 

[Dellmassive]

That's a really neat nightlight

Love it.

 

[CJW]

Love it.

Chief advisor’s idea. Can’t take credit.

 

[Dellmassive]

looks great . . . got a link for it?


...


we`ve been using a RED USB lamp left on overnight..
.
.

 

[moomin-j]

looks great . . . got a link for it?


...


we`ve been using a RED USB lamp left on overnight..
.
.


View attachment 214732View attachment 214733

Reminds me of a happy place in Amsterdam

 

[CJW]

Worth saying I had a torch on to be able to photograph the panels last night. The yellow light itself is very subtle - more like ambient cab lighting. Dead cheap from eBay:

1 x 6mm LED DASH PANEL WARNING LIGHT 12V CAR VAN LORRY BIKE BOAT WARNING SS UK | eBay

Mounting Hole Size: 6mm(Approx.). YOU GET A LED IN YOUR CHOICE OF COLOUR SENT OUT IN JIFFY TYPE ENVELOPE. Light Colour: Yellow / Blue / Green / White / Red (As pictures show). Working Temperature: -20degree Celsius ~ + 55degree Celsius.

www.ebay.co.uk

 

[roadtripper]

I've used these before - 3mm leds in a deep chrome bezel - they make for a very low glare projected directional glow for more ambient type lighting. I'd like to put some up in the Caravelle but the though of disturbing all the stock headlining and ventilation there puts me off...

BRIGHT RED 12V LED (3mm) WITH CHROME BEZEL 3538056656713 | eBay

Find many great new & used options and get the best deals for BRIGHT RED 12V LED (3mm) WITH CHROME BEZEL at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[lucysd]

The Renogy one is excellent and on offer at the moment on Amazon:

Would another Renogy monitor do the same excellent job when connected to the Renogy Smart Lithium battery? Talking about this model:

Monitoring Screen for Smart Lithium Battery Series

Renogy offers premium solar panels, inverters, lithium batteries, and solar charge controllers for off-grid solar systems in the EU. Shop with confidence for top-quality products, expert guidance, and exceptional customer support to meet your energy requirements.

eu.renogy.com

Or smart shunt version is more precise/correct?

 

[CJW]

Would another Renogy monitor do the same excellent job when connected to the Renogy Smart Lithium battery? Talking about this model:

Monitoring Screen for Smart Lithium Battery Series

Renogy offers premium solar panels, inverters, lithium batteries, and solar charge controllers for off-grid solar systems in the EU. Shop with confidence for top-quality products, expert guidance, and exceptional customer support to meet your energy requirements.

eu.renogy.com

Or smart shunt version is more precise/correct?

I’m sorry I don’t know anything about the lithium one. Happy to dive in later when I get chance. Others may know.

 

[CJW]

I’m not overly familiar with Lifepo batteries but the link you included above states that the data the monitor displays is directly from the BMS, which would make it, in theory, more accurate than a shunt can be - it’s the actual state as seen by the battery rather than an implied figure.