IP Blue 30a Charger high voltage issue 15.7v?

[postaldust]

Good day.

I have set up VE Networking using victron SmartShunt and am charging 12v LiFePO4 battery via an IPBlue 30A charger.

The IPBlue profile is set to the default Smart LiFePO4 profile; however, while connecting to VE Networking, the IPBlue is pushing a high voltage of up to 15.7V.
There is about 23 feet (7 meters) between the battery and the charger. Is this normal? see screenshots

 

[sunshine_eggo]

Depending on the gauge of your wire and the quality of your connection, yep.

 

[sunshine_eggo]

If you used 10awg, and your connections are excellent, you'd see a 1.23V drop between the two. Since you're notably worse, I expect you have bad connection(s).

 

[MakeMePower]

If you used 10awg, and your connections are excellent, you'd see a 1.23V drop between the two. Since you're notably worse, I expect you have bad connection(s).

are you saying the victron is artificially raising the voltage to deal with the voltage drop and will later lower it to a preset voltage?

 

[sunshine_eggo]

are you saying the victron is artificially raising the voltage to deal with the voltage drop and will later lower it to a preset voltage?

No. It's not artificial at all. AT the charger, it's 15.7V. By the time it gets to the battery, it's lost 2.2V due to wiring/connection losses.

If you could tap into the leads AT the charger, you would measure 15.7V with a voltmeter.

Put another way... 2.2V * 26.8A = 58.96W = the amount of power you're losing in your wires.

The charger clearly has a limit, and I'm guessing that since it's under 30A, the limit is 15.7V. It will continue to hold 15.7V, and as the battery voltage rises, the current will drop. Once the battery hits 14.2V, the charger will further regulate its output to hold the battery at 14.2V. Once the current drops to near zero, they will both read 14.2V, though the charger will be a touch higher.

 

[MakeMePower]

No. It's not artificial at all. AT the charger, it's 15.7V. By the time it gets to the battery, it's lost 2.2V due to wiring/connection losses.

If you could tap into the leads AT the charger, you would measure 15.7V with a voltmeter.

Put another way... 2.2V * 26.8A = 58.96W = the amount of power you're losing in your wires.

The charger clearly has a limit, and I'm guessing that since it's under 30A, the limit is 15.7V. It will continue to hold 15.7V, and as the battery voltage rises, the current will drop. Once the battery hits 14.2V, the charger will further regulate its output to hold the battery at 14.2V. Once the current drops to near zero, they will both read 14.2V, though the charger will be a touch higher.

i understand the loss, where is this setting configured in VE connect, I am playing with a demo, but in user settings where is this voltage compensation set somewhere? i see temp compensation ,but nothing other then reconditioning voltage adjustments?

 

[sunshine_eggo]

i understand the loss, where is this setting configured in VE connect, I am playing with a demo, but in user settings where is this voltage compensation set somewhere? i see temp compensation ,but nothing other then reconditioning voltage adjustments?

There's no such thing. This is simply Ohms law. The charger is set to charge to 14.2V @ 30A. That's what it's trying to do. The wiring/connections are forcing it to supply 15.7V in an effort to get to 30A @ 14.2V.

If you want to lower the output voltage, you need to lower the current.

 

[MakeMePower]

There's no such thing. This is simply Ohms law. The charger is set to charge to 14.2V @ 30A. That's what it's trying to do. The wiring/connections are forcing it to supply 15.7V in an effort to get to 30A @ 14.2V.

If you want to lower the output voltage, you need to lower the current.

yes but normal chargers don't typically boost the voltage, i guess this is the uniqueness of the smart shunt. i thought there might be some setting adjustments here, but I can see now its not really necessary. none of the manuals really speak to it

 

[sunshine_eggo]

yes but normal chargers don't typically boost the voltage, i guess this is the uniqueness of the smart shunt. i thought there might be some setting adjustments here, but I can see now its not really necessary. none of the manuals really speak to it

It's a function of the separate voltage sense, and it's pretty common for chargers capable of being fed a direct voltage measurement.

This is a pretty extreme example. The losses are pretty huge and way beyond what would normally be considered acceptable.

 

[MakeMePower]

It's a function of the separate voltage sense, and it's pretty common for chargers capable of being fed a direct voltage measurement.

This is a pretty extreme example. The losses are pretty huge and way beyond what would normally be considered acceptable.

yea, apparently i was reading the data sheet, it speaks to it in the manuals

 

[postaldust]

yes but normal chargers don't typically boost the voltage, i guess this is the uniqueness of the smart shunt. i thought there might be some setting adjustments here, but I can see now its not really necessary. none of the manuals really speak to it

I believe Multiplus also has automatic voltage adjustment while using VeNetwork

 

[sunshine_eggo]

I believe Multiplus also has automatic voltage adjustment while using VeNetwork

Since there are four separate Victron network types (VE.Bus, VE.CAN, VE.Direct, VE.Smart), I'll assume you intended VeNetwork to indicate a bluetooth VE.Smart network.

The only way the MP can get a direct voltage measurement is:

1) sense wires from the battery to its V-sense terminals.
2) from a GX connected source like a shunt or BMS (supplied by the VE.Bus connection to the GX).
3) from a VE.Bus smart dongle.

It cannot receive ANY data over bluetooth even with the smart dongle. The smart dongle can share voltage and temperature data with MPPT in the VE.Smart network.

 

[postaldust]

This is the last screenshot when the battery was almost fully charged. I get the impression that the voltage pattern is more suited to an AGM battery profile.

 

[sunshine_eggo]

This is the last screenshot when the battery was almost fully charged.

I suspect it's hot and throttling back its output.

I get the impression that the voltage pattern is more suited to an AGM battery profile.

Why?

 

[postaldust]

Why?

I thought it was compensating for the voltage loss by rising to 15.7, but in the last screen, the voltage was reduced to 14.5

 

[sunshine_eggo]

I thought it was compensating for the voltage loss by rising to 15.7, but in the last screen, the voltage was reduced to 14.5

That's why I'm saying I think it's derated itself due to heat.

 

[mikefitz]

I have set up VE Networking using victron SmartShunt and am charging 12v LiFePO4 battery via an IPBlue 30A charger.

Way back in September you asked about the same issue of high voltage at the charger output,

P

Thread 'Lifepo4 Victron charger voltage increased to 15.2v after joining VeSmart network'

Sep 3, 2024

After joining the Victron shunt and two Bluesmart IP22 (30a) chargers to the Ve.smart network to charge a 760Ah LiFePO4 battery, the voltage of both Bluesmart units increased to 15.2V (see picture).
Both chargers have identical profiles set to the Smart Lithium (LiFePO4) default Victron profile, with the voltage set at 14.2V.

The only thing I can think of is voltage compensation between the charger and the battery is about 23 feet (7 meters).
Has anyone had any experience with this?

• postaldust
• Replies: 7
• Forum: General Battery Discussion

In an earlier post you had problems connecting two 30A chargers in parallel. ( my guess is that not all charge current was passing through the shunt).

The increase in charger volts over battery volts seems to be due to resistance in the circuit in the positive or negative path, or both, and is resionably consistent. At 26.8 amps the drop was 2.18 volts, path resistance 0.081 ohms, at 7.5 amps the drop was 0.7 volts, path resistance 0.093 ohms.
In the earlier posts there was a suggestion of adding diodes, it would be useful to have more details, a circuit diagram, details of what is between the charger and battery, ( wire gauge, fuses or breakers,). Pictures often help.

My guess is 10AWG cable ( 6mm2)