straight back to the installer something is not right ! my alternator can run up to 14.7 to 14.8 v at times and never had a problem, same projecta dc - dc charger as you .
straight back to the installer something is not right ! my alternator can run up to 14.7 to 14.8 v at times and never had a problem, same projecta dc - dc charger as you .
No surpises here, bloke that installed it has ****ed everything he has touched.
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Kevin Kyle
On the road full time with Son and 21 year old cat and 3 year old Manx.
Toyota Landcruiser 100 series V8. Nextgen semi off-roader. 3 120 AH agm batteries, 1KW Solar
Should the charger be connected to or through ignition directly in the first place ? Imo it should be through accessories or relay ? Double check what DC -DC recoment . On EFI or electronic ignition they should be seperate . Check wiring diagram. Adding load here is overloading circuit !!
Should the charger be connected to or through ignition directly in the first place ? Imo it should be through accessories or relay ? Double check what DC -DC recoment . On EFI or electronic ignition they should be seperate . Check wiring diagram. Adding load here is overloading circuit !!
Alternator power is controlled by relay, not Redarc, but similar, also used to charge Ark battery box in the car, off same circuit. It also has 30 amp fuse with no problems. Is wired as per the circuit diagram in the Projecta manual.
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Kevin Kyle
On the road full time with Son and 21 year old cat and 3 year old Manx.
Toyota Landcruiser 100 series V8. Nextgen semi off-roader. 3 120 AH agm batteries, 1KW Solar
Thanks AK, yes I have double checked with with the bloke that did the car installation, the car installation is correct.
I have looked at the cable the van installer has used and it appears to be as per the manual. The cable that is used for smart alternator appear to have been removed and the red ignition cable is the one connected via Anderson plug to the alternator.
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Kevin Kyle
On the road full time with Son and 21 year old cat and 3 year old Manx.
Toyota Landcruiser 100 series V8. Nextgen semi off-roader. 3 120 AH agm batteries, 1KW Solar
Is the ignition circuit taking the full load ? Amps ??
In the van wiring?
Blowing fuse 30 amp. in the van. Car wiring checked by Autospark and all good.
There is no need for a fuse in the van. I would only put a fuse near the battery supplying the load. In this case the battery is in the tug. A fuse at the input to the charger will not protect the charger. Thay do not make readily available fuses that act that quickly. The only fuse that is necessary is the one that will blow if there is a fault in the supply cable. Every fuse you have in line increases the voltage drop a smidgen. I would be inclined to remove the one in the van. The one in the tug should be rated at 50 A.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
Is the ignition circuit taking the full load ? Amps ??
In the van wiring?
Blowing fuse 30 amp. in the van. Car wiring checked by Autospark and all good.
There is no need for a fuse in the van. I would only put a fuse near the battery supplying the load. In this case the battery is in the tug. A fuse at the input to the charger will not protect the charger. Thay do not make readily available fuses that act that quickly. The only fuse that is necessary is the one that will blow if there is a fault in the supply cable. Every fuse you have in line increases the voltage drop a smidgen. I would be inclined to remove the one in the van. The one in the tug should be rated at 50 A.
No Peter, the battery is NOT in the tug. The manufacturer clearly states that the 50amp circuit breaker must be in the van in the ignition feed cable. I spoke to tech support as above and that was their instruction. THe manual also clearly states this.
To put it simply, rip off unqualified installer.
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Kevin Kyle
On the road full time with Son and 21 year old cat and 3 year old Manx.
Toyota Landcruiser 100 series V8. Nextgen semi off-roader. 3 120 AH agm batteries, 1KW Solar
FWIW... not an uncommon mistake to make and might not cause an issue for most, that is using a 30 amp fuse for a 25amp DC2DC charger.
If your voltage drop leading to the charger is small, you may not have an issue (such as an under bonnet dc2dc fed with a meter or two of 10mm plus cable). But with one in a van hanging off 10-12m of cable, there will be a bit more voltage drop across the cable feeding it, so the dc2dc charger will need to draw more current to produce it's output voltage and current.... I tend to go at least 40a on a 25a unit.
Also worth having a fuse protecting the van cable near its inlet plug..... some day the van may be plugged into a vehicle wired with, say 25mm plus cable and fused at a much higher amperage.
-- Edited by Noelpolar on Friday 31st of August 2018 09:30:52 AM
-- Edited by Noelpolar on Friday 31st of August 2018 09:38:18 AM
-- Edited by Noelpolar on Friday 31st of August 2018 09:38:47 AM
This is basically a repeat of what has already been posted but for some reason this post got stuck in the pipeline when I shut my computer down yesterday afternoon.
The most common problem we have when it comes to DC to DC chargers is the installer using an under rated fuse or poor fuse/holder design or using a circuit breaker rather than a fuse. 6 B&S cable can handle a 100 amp load without melting or catching on fire so what is the logic in fitting a 30 amp fuse? A fuse is only there to protect the cable run, not the appliance, if the appliance has a fire risk in the case of a short circuit it has its own internal fuses rated to protect against that problem so adding an under rated fuse/circuit breaker in the supply end of the cable is just dumb. It seems many installers have forgotten ohms law when it comes to cable size requirement and fuse rating. If the DC to DC charger can produce 25 amps @ 14.4v the output is 360w. Add 10% for conversion losses within the equipment and the requirement on the input side is up around 400W. If the unit will function at a voltage as low as 9v say, then 400w divided by 9v = approx. 45 amps. That is the current required at the supply end on a continuous basis, a 30 amp fuse or circuit breaker isn't going to meet that requirement, even a 50 amp fuse is getting close to its limit and a 50 amp circuit breaker of the type often used by installers for DC circuits most certainly won't handle the heat generated through the bi-metal strip on a long term basis. Now add the arcing across the contacts each time it trips and resets increasing the resistance and the once rated 50 amp circuit breaker drops to 30 amps or less after 15 mins and useless for the job.
A 60 amp midi fuse and holder will minimise the poor connection heat generated by many fuse/holder types and have enough overhead capacity to prevent nuisance failures, yet well within the safety limits of the cable it is designed to protect.
T1 Terry
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This is basically a repeat of what has already been posted but for some reason this post got stuck in the pipeline when I shut my computer down yesterday afternoon. The most common problem we have when it comes to DC to DC chargers is the installer using an under rated fuse or poor fuse/holder design or using a circuit breaker rather than a fuse. 6 B&S cable can handle a 100 amp load without melting or catching on fire so what is the logic in fitting a 30 amp fuse? A fuse is only there to protect the cable run, not the appliance, if the appliance has a fire risk in the case of a short circuit it has its own internal fuses rated to protect against that problem so adding an under rated fuse/circuit breaker in the supply end of the cable is just dumb. It seems many installers have forgotten ohms law when it comes to cable size requirement and fuse rating. If the DC to DC charger can produce 25 amps @ 14.4v the output is 360w. Add 10% for conversion losses within the equipment and the requirement on the input side is up around 400W. If the unit will function at a voltage as low as 9v say, then 400w divided by 9v = approx. 45 amps. That is the current required at the supply end on a continuous basis, a 30 amp fuse or circuit breaker isn't going to meet that requirement, even a 50 amp fuse is getting close to its limit and a 50 amp circuit breaker of the type often used by installers for DC circuits most certainly won't handle the heat generated through the bi-metal strip on a long term basis. Now add the arcing across the contacts each time it trips and resets increasing the resistance and the once rated 50 amp circuit breaker drops to 30 amps or less after 15 mins and useless for the job. A 60 amp midi fuse and holder will minimise the poor connection heat generated by many fuse/holder types and have enough overhead capacity to prevent nuisance failures, yet well within the safety limits of the cable it is designed to protect.
T1 Terry
I could not agree more
Follow Terry's advice
Just make sure ,that at no point ,are supply cables rated lower than the fuse
-- Edited by oldtrack123 on Friday 31st of August 2018 04:24:28 PM
Correct me if I am wrong . Itâs blowing ignition feed fuse . Is the standard wireing being used ? I highly doubt it would be 50 amp rated . Is it using this circuit to trip relay ?
Blowing fuse 30 amp. in the van. Car wiring checked by Autospark and all good.
There is no need for a fuse in the van. I would only put a fuse near the battery supplying the load. In this case the battery is in the tug. A fuse at the input to the charger will not protect the charger. Thay do not make readily available fuses that act that quickly. The only fuse that is necessary is the one that will blow if there is a fault in the supply cable. Every fuse you have in line increases the voltage drop a smidgen. I would be inclined to remove the one in the van. The one in the tug should be rated at 50 A.
No Peter, the battery is NOT in the tug. The manufacturer clearly states that the 50amp circuit breaker must be in the van in the ignition feed cable. I spoke to tech support as above and that was their instruction. THe manual also clearly states this.
When I said "I would only put a fuse near the battery supplying the load. In this case the battery is in the tug" I was referring to the battery supplying the power to the charger. That is in the tug and should be charged by the alternator when the DC-DC charger is operating.
The underlying principle of good circuit design is to keep the number of fuses to a minimum. Having two fuses in the one circuit that connects a battery with a load is pure stupidity. The one fuse shouild be close to the voltage source, ie the battery. (However, if there is a battery at each end of the line you should have a fuse at each battery.) This principal has applied over the 50 plus years I have been dealing with electrics. Putting a second fuse in line causes confusion when people are diagnosing problems, they do not expect extraneous fuses to be in line. Handbooks dealing with devices like this often picture a fuse at the input to the device, it is put there to remind people that a fuse is required between the battery and the device and not that two fuses are required.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
) is 50w
