Jump to content

How accurate is my Smartgauge?


MtB

Featured Posts

Depends which one! I have two.

Both my Smartgauges are now connected to the same battery bank. The newer gauge has been connected for three weeks to make sure it had time to calibrate itself to the bank. Here is a list of simultaneous readings on both gauges, taken at random times over the last few days:

 

Gauge 1 / gauge 2

100/100
99/92
89/72
75/58
89/74
100/88
100/100
100/99
95/84
100/93
100/100
87/71
82/64
79/60
86/70
83/64
83/66
85/68
100/99
98/90
 

Discuss... as they say.

Link to comment
Share on other sites

you have previously stated that gauge 1 is out of calibration and the volts reading is high. Gauge 2 may well be correct this could explain why your batteries have lost capacity as you have not been recharging them to the level you thought.

 

Link to comment
Share on other sites

On 07/04/2017 at 05:16, Loddon said:

you have previously stated that gauge 1 is out of calibration and the volts reading is high. Gauge 2 may well be correct this could explain why your batteries have lost capacity as you have not been recharging them to the level you thought.

 

Yes I see your point. But there is more. The voltage displayed by the old gauge is approx 0.3v high, using a correctly calibrated voltmeter. The voltage displayed by the new Smartgauge is approximately 0.3v low, using the same correctly calibrated voltmeter.

Conclusion: You can't trust a Smartgauge straight from the box. I now have two, both calibrated wrongly!

Edited by Mike the Boilerman
Link to comment
Share on other sites

It would be good to see some figures down towards 50% as the Smartgage is allegedly most accurate in this region.

We know its not perfect during charging and mine certainly takes a little while to get its act together just after a charge, so the errors at 90 to 100% are possibly to be expected.

As for calibration, it is of course possible that my reference, my voltmeter and all of your voltmeters have all drifted in the same direction. Maybe we should pay for a visit to the National Physics Lab and get it checked against the national standard?, but then maybe their standard has drifted too  :D  The NPL is actually only a shortish walk from Teddington lock so conveniently located for boaters with calibration issues, I will add this to my list of jobs that will never get done.

................Dave

Link to comment
Share on other sites

To bring this exciting experiment to its conclusion I feel the methodology MUST include testing every Smartgauge ever produced with test equipment that MUST be re-calibrated between each test by test equipment that MUST be calibrated between each........

Good grief.....

Link to comment
Share on other sites

I don't know why Mike hasn't contacted Merlin about it as I suggested to him many months ago. 

If they're being supplied miscalibrated and it matters then the whole quality control needs looking at and Mike's units need to be fixed. If 0.3V doesn't matter then they could let him know that too. 

It certainly appears to me that the one which over-reads is displaying SoC too high, and the one which under-reads displays SoC too low. This is what I'd expect. 

Link to comment
Share on other sites

6 minutes ago, Dave Payne said:

Buy more solar and forget about battery woes till October!

Buy more beer and forget about batteries altogether. 

 

ETA

I'd have to get a beergauge then to tell me when I'm below 50%.

 

Edited by rusty69
Link to comment
Share on other sites

2 minutes ago, roland elsdon said:

Throw smart gauge in cut

buy cheapest batterys

Charge " when you can be bothered "or when lights dim repeat repeat repeat

when time spent from charge to light goes dim is 50% shorter replace batteries.

thats what's going to happen anyway.

This ^^^^^^

Just worked out that our last set of cheapo batteries cost us £150 for the pair and lasted four years. That is 72p per week.

Not worth worrying about. When they are not up to the job anymore give them away and get a new set. No fancy monitoring, no checking on them once a day, no checking SG's. Just fit and forget.

Link to comment
Share on other sites

1 minute ago, Naughty Cal said:

This ^^^^^^

Just worked out that our last set of cheapo batteries cost us £150 for the pair and lasted four years. That is 72p per week.

Not worth worrying about. When they are not up to the job anymore give them away and get a new set. No fancy monitoring, no checking on them once a day, no checking SG's. Just fit and forget.

Wind em up and let em go! 

Link to comment
Share on other sites

There have been a number of threads recently about charging batteries and sulphation.

I have got the impression that, to minimise sulphation, best practise is to charge every day or failing that, as often as you possibly can. The Smartgauge then reverts to being an indication of how charged your batteries are, expressed as a percentage, in which case the unit that displays a lower than actual state is the one to retain.

Link to comment
Share on other sites

30 minutes ago, peterboat said:

I knew I had made the right decision when I bought my NASA BM2 plus it shows amps in and out which I need cos my midnight has a control panel in the cupboard

But how do you know when the batteries are at 50% (or whatever % you like to charge from), amp counters are totally inaccurate at this.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.