Digital Volt Meter

[dougmcp]

Originally Posted by AzPete

I was wondering why I would want the bar graph left in.......it reads 1/2 when the cart stops operating......

You probably had one of the cheap Chinese $25 knock offs which are not calibrated properly, they show a full charge when your batteries are almost dead.
The ones that have been around for years are made by Curtis and cost in the $75 range. They work extremely well, reset every time you recharge and generally never quit.

As a side note: What you have ordered is a voltmeter that gives you an instant voltage reading, when you step on the throttle it will drop 15% then it will rebound and give you any reading between 85% (32.5v) and 95% (36.2v) depending on where the throttle is positioned and when you stop and rest the batteries for 5 minutes it will pop back up to 100% (38.2v).
This whole scenario makes it difficult for the layman to assess state of charge until you stop and rest the batteries. Even then there is no full, 1/2, empty reading so you have to remember after resting what voltage you have to have to get home.
To me the best scenario is to have both meters.
I think the whole concept of a state of charge meter is a little misunderstood.
It is not a voltmeter, it is a gauge that stays constant and measures a percentage of charge remaining based on the initial input (charge). They essentially take a pre-established level of charge and determine the percentage remaining. If the initial input was 38.2v it would start from that set point, if it was 38.6v it would start there.
Each bar on a Curtis meter represents 8% of the charge so when it drops to the second bar from full the amount remaining is between 86% and 92% of a full charge.
In a nutshell the state of charge meter is not as accurate as a voltmeter, it is just more convenient and consistent without having to remember any voltage numbers.

[scottyb]

Technical information test about your battery pack & those hard to remember numbers ...

If 38v is full and 36 is empty.

Can anybody tell me what half full is?

Okay it gets harder now. Can anybody tell me what 3/4 full is?


Those bar graph meters are on all the old carts. I've taken the time to test a few side by side with the harder to read digital voltmeter. It is test results like this that made look for an alternative in the first place. I hope this helps (not too technical) I had a truck with a gas gauge like this once...... read full for days and dropped like a stone.

[rib33024]

1/2 is 37 - and - 3/4 is 37.75

[scottyb]

Originally Posted by rib33024

1/2 is 37 - and - 3/4 is 37.75

Look at that.

Even a gas cart guy can do it

It's not rocket science now is it. I like the handy load tester constantly connected to the pack.... getting a weak battery? Developing a bad cell? If you know your cart you will see it coming.
To each their own preference, that is why there both of these types and there is analog too ...... we have choices.

[AzPete]

Well, if I have a chinese knockoff, they spelled Curtis correctly. I was told I am the third owner and the guy I got it from had the same comment about the meter and he did not install it. My bet is it has been on there for a while.

Today's use of the cart was pretty hard. I am towing cut trees about 500 feet threw soft dirt (5-6 2"-5" trees, 30 feet tall and skinny and two adults on the cart) plus running items for the guys cutting the trees. It went from full reading to 1 bar down....ok. Then it suddenly dropped another bar in about 1/5th of the time it took for the first drop in the reading. Dropped to the next bar fast too. Still had good power and speed. Plugged in the charger and in 3.5 hours, bars are restored and the charger is down to about 4 amps from just below a 20 amp start.

The uneven drop is what I have seen a few times now. That makes me wonder on the accuracy when planning the trip home without a tow involved. Being our first cart, I don't want to give mama any reason to doubt the purchase....lol

Oh, and as to remembering numbers....at what percentage is the least.....and each bar is 8% of the starting voltage that I do not know without measuring......hmmmm....numbers seem real easy to me.

[Coltf1991]

Originally Posted by scottyb

Look at that.

Even a gas cart guy can do it

Originally Posted by AzPete

Well, if I have a chinese knockoff, they spelled Curtis correctly. I was told I am the third owner and the guy I got it from had the same comment about the meter and he did not install it. My bet is it has been on there for a while.

Today's use of the cart was pretty hard. I am towing cut trees about 500 feet threw soft dirt (5-6 2"-5" trees, 30 feet tall and skinny and two adults on the cart) plus running items for the guys cutting the trees. It went from full reading to 1 bar down....ok. Then it suddenly dropped another bar in about 1/5th of the time it took for the first drop in the reading. Dropped to the next bar fast too. Still had good power and speed. Plugged in the charger and in 3.5 hours, bars are restored and the charger is down to about 4 amps from just below a 20 amp start.

The uneven drop is what I have seen a few times now. That makes me wonder on the accuracy when planning the trip home without a tow involved. Being our first cart, I don't want to give mama any reason to doubt the purchase....lol

Oh, and as to remembering numbers....at what percentage is the least.....and each bar is 8% of the starting voltage that I do not know without measuring......hmmmm....numbers seem real easy to me.

I dont care what brand they are, chinese, curtis, japanese, americanese..... i think they all suck.

Why do people make these digital meters out to be something they are not. Its simple.

Now if you want something hard to read and keep track of watch the wideband on my cammed srt-4. LOL you cant keep up with the air to fuel ratio. Especially at idle.

[dougmcp]

Originally Posted by scottyb

Technical information test about your battery pack & those hard to remember numbers ...

If 38v is full and 36 is empty.

Can anybody tell me what half full is?

Okay it gets harder now. Can anybody tell me what 3/4 full is?


Those bar graph meters are on all the old carts. I've taken the time to test a few side by side with the harder to read digital voltmeter. It is test results like this that made look for an alternative in the first place. I hope this helps (not too technical) I had a truck with a gas gauge like this once...... read full for days and dropped like a stone.

You're right Scotty it gets more technical the deeper you get into it.
Based on manufacturers suggestions of not going below 80% discharged and using the Trojan state of charge chart, a full pack is 38.2v (38v for the theory part) and 34v is a completely discharged pack (Dead = 0.5v below the 10% number of 34.5v)

The numbers (rounded to 0.1v) on the Curtis Model 906 State of Charge meter are:

Bar 10: 92%-100% = 37.7v-38v

Bar 9: 86%-92% = 37.4v-37.7v

Bar 8: 78%-86% = 37.1v-37.4v

Bar 7: 70%-78% = 36.8v-37.1v

Bar 6: 62%-70% = 36.5v-37.1v

Bar 5: 56%-62% = 36.2v-36.5v

Bar 4: 48%-56% = 35.9v-36.2v

Bar 3: 40%-48% = 35.6v-36.2v

Bar 2: 30%-40% = 35.2v-35.6v

Bar 1: 20%-30% = 34.8v-35.2v

No Bars: Dead at 34v.

I have a chart and data log from my cart but it is 48v and not good for this 36v test question.

Speaking of gas gauges, I have an Expedition that runs for 75 miles on full then it too drops like a stone. As soon as it starts going down it reminds me of how expensive that thing is to drive at 15mpg.

In the end Scotty is right, all these meters have their uses. I use both but the voltmeter is the most informative to me.

[rib33024]

2 - #2s no #6 ?

[madoc1]

Originally Posted by dougmcp

You're right Scotty it gets more technical the deeper you get into it.
Based on manufacturers suggestions of not going below 80% discharged and using the Trojan state of charge chart, a full pack is 38.2v (38v for the theory part) and 34v is a completely discharged pack (Dead = 0.5v below the 10% number of 34.5v)

The numbers (rounded to 0.1v) on the Curtis Model 906 State of Charge meter are:

Bar 10: 92%-100% = 37.7v-38v

Bar 9: 86%-92% = 37.4v-37.7v

Bar 8: 78%-86% = 37.1v-37
Bar 7: 70%-78% = 36.8v-37.1v

Bar 6: 62%-70% = 36.5v-37.1v

Bar 5: 56%-62% = 36.2v-36.5v

Bar 4: 48%-56% = 35.9v-36.2v

Bar 3: 40%-48% = 35.6v-36.2v

Bar 2: 30%-40% = 35.2v-35.6v

Bar 1: 20%-30% = 34.8v-35.2v

No Bars: Dead at 34v.

I have a chart and data log from my cart but it is 48v and not good for this 36v test question.

Speaking of gas gauges, I have an Expedition that runs for 75 miles on full then it too drops like a stone. As soon as it starts going down it reminds me of how expensive that thing is to drive at 15mpg.

In the end Scotty is right, all these meters have their uses. I use both but the voltmeter is the most informative to me.

i know it is a 36v discussion, but some of us would love to see the 48v info also. pls?

[segdoh49]

Originally Posted by AzPete

Good info....now, if the meter can make the coast to coast trip.....

Stay away from the east coast, too many EARTHQUAKES. !!!