Vsr stops sending to carnarvan

Rowan · Member

Vsr stops sending to carnarvan

PeterD · Guru

Probably has something to do with a smart alternator dropping to an output voltage that will not hold the relay in. How old is the Pathfinder?

oldtrack123 · Guru

PeterD wrote:
Probably has something to do with a smart alternator dropping to an output voltage that will not hold the relay in. How old is the Pathfinder?

Very likely the reason.

Need to check the specs for the VSR

Some do need a rather high voltage to continue to hold in

A quick check it seems you have one that drops out @12.7V

Problems using that one with smart alternators.

The best option is to have the alternator voltage boosted ,as 12.7 v will do little to charge remote van battery/s

-- Edited by oldtrack123 on Wednesday 25th of April 2018 05:47:30 PM

Rowan · Member

It's a 2012 pathfinder. The last of the r51 models. The narva vsr i used is a 61092BL 140 amp charges between 12.7v and 13.3v.

Rowan · Member

What's the best way to check what my alternater is putting out. Multimeter?

Rowan · Member

How would i bost the alternator voltage if that's the problem?

PeterD · Guru

Rowan wrote:
What's the best way to check what my alternater is putting out. Multimeter?

Cigarette Lighter Battery Monitor - plug it into one of your cigarette lighter sodkets so you can observe it whilst you are able to observe it whilst you are driving.

Jaahn · Guru

Rowan wrote:
How would i bost the alternator voltage if that's the problem?

Hi Rowan smile

With that output voltage from your alternator it will not charge your van battery anyway, it is designed to only keep the Nissan battery recharged after starting. Not sure why they are called "smart alternators" disbelief

So you will have to fit a DC to DC charger which boosts the tug battery voltage to a suitable voltage for charging the van battery and pushing it along the wires too. Google them up as I do not use one myself. They are common now for use on the new tugs. hmm

Jaahn

Rowan · Member

Yes the volts started at 14v but after a few minutes it went below 2.7v and staying there for the rest of the trip.

Rowan · Member

Hi guys i found that by leaving the head lights on the volts sit on 13v. Which is right in the middle of the vsr operating range.

PeterD · Guru

13 V is still too low to charge a battery. You need up around 14 V.

Jaahn · Guru

PeterD wrote:
13 V is still too low to charge a battery. You need up around 14 V.

Hi smile

I agree. The battery will never be charged and fail quickly. Really you need 14 ++ volts for some time to completely charge a deep cycle battery that is cycling every day and then it should drop to a lower float voltage, 13.8v or so for maintaining it.

So the DC to DC charger should have a three stage charging protocol just like a solar or 240V charger to keep it working well. aww

Jaahn