Had a Projecta 25amp DC-DC charger fitted to caravan.
Solar input works fine, but the ignition feed keeps blowing the 30 amp fuse.
Output from the Alternator is 14.2 volts.
outlaw40 said
11:59 AM Aug 29, 2018
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 .
Snippy said
12:02 PM Aug 29, 2018
outlaw40 wrote:
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.
Aus-Kiwi said
12:03 PM Aug 29, 2018
Is the ignition circuit taking the full load ? Amps ??
Snippy said
12:05 PM Aug 29, 2018
Aus-Kiwi wrote:
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.
Aus-Kiwi said
12:16 PM Aug 29, 2018
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 !!
Aus-Kiwi said
12:21 PM Aug 29, 2018
Is your vehicle equipped with ecu controlled voltage reg ?
Snippy said
12:22 PM Aug 29, 2018
Aus-Kiwi wrote:
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.
Aus-Kiwi said
12:30 PM Aug 29, 2018
Ok just thought the ignition wire was only for smart - ECU controlled alternator ??
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.
Snippy said
12:44 PM Aug 29, 2018
I note that the input fuse raring (rating, bit old to be raring fuses) is 50w
-- Edited by Snippy on Wednesday 29th of August 2018 12:57:38 PM
Snippy said
01:15 PM Aug 29, 2018
Hi all, Thanks for your input.
I have just spoken with Projecta tech support, (Brown and Watson).
The ignition feed fuse should be 50amp circuit breaker. The installer has has used a 30 amp inline fuse on 30amp cable.
I am tempted to name the idiot installer, but softly softly for now.
denmonkey said
03:45 PM Aug 30, 2018
Snippy wrote:
I am tempted to name the idiot installer, but softly softly for now.
good call I think.
I have the ID25 in my pajero and I'm pretty sure the instructions called for a 30amp breaker/fuse.
I checked the online install instructions and it says 50amp.
So I'm thinking it may have changed at some point and he may very well have followed the older instruction.
That being said, I used a 30amp and had no issues with it tripping or causing any issues.
Not sure if that helps any
Warren-Pat_01 said
07:10 PM Aug 30, 2018
Snippy,
Just be aware that there are two types of cct breakers - auto-resetting & manual resetting - the latter gives you better control of any fault.
I have seen a disastrous issue with an auto where the people involved weren't aware of a problem until they stopped & saw smoke!
PeterD said
08:25 PM Aug 30, 2018
Snippy wrote:
Aus-Kiwi wrote:
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.
Aus-Kiwi said
08:30 PM Aug 30, 2018
Yep . Assuming cable / wire is heavy enough ?
Snippy said
08:37 PM Aug 30, 2018
denmonkey wrote:
Snippy wrote:
I am tempted to name the idiot installer, but softly softly for now.
good call I think.
I have the ID25 in my pajero and I'm pretty sure the instructions called for a 30amp breaker/fuse.
I checked the online install instructions and it says 50amp.
So I'm thinking it may have changed at some point and he may very well have followed the older instruction.
That being said, I used a 30amp and had no issues with it tripping or causing any issues.
Not sure if that helps any
The manual he was given said 50w. The bloke is a cowboy. RV Builder in Beaudesert(Ooops slipped out)
Snippy said
08:51 PM Aug 30, 2018
PeterD wrote:
Snippy wrote:
Aus-Kiwi wrote:
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.
swamp said
07:07 AM Aug 31, 2018
HI
Alternator/ battery feed =50amp fuse
Ignition override sense wire [to remotely turn unit on/off ] fused 1-2 amps
Snippy said
08:21 AM Aug 31, 2018
swamp wrote:
HI Alternator/ battery feed =50amp fuse Ignition override sense wire [to remotely turn unit on/off ] fused 1-2 amps
Hi Swamp, yes as per the manual, too easy, well for most of us.
Noelpolar said
09:27 AM Aug 31, 2018
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
T1 Terry said
11:05 AM Aug 31, 2018
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
oldtrack123 said
04:20 PM Aug 31, 2018
T1 Terry wrote:
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
Snippy said
05:52 PM Aug 31, 2018
T1 Terry, Exactly what the guy at Jaycar said today and has supplied the circuit breaker (60 amp) and 50 amp cable to complete the connection.
Thanks everyone for your input. Will hook it up tomorrow and let you now how it all goes.
Aus-Kiwi said
07:35 PM Aug 31, 2018
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 ?
PeterD said
09:21 PM Aug 31, 2018
Snippy wrote:
PeterD wrote:
Snippy wrote: 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.
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.
Aus-Kiwi said
10:03 PM Aug 31, 2018
Except starter motors . Cable is sufficient!! Lol mind you fuse is a great isolation device ..
Snippy said
04:24 AM Sep 1, 2018
Hi Peter,
(However, if there is a battery at each end of the line you should have a fuse at each battery.)
Yes it is the second battery the one in the van that has the wrong fuse.
Projecta tech support bloke said this needs to be 50 watt amp circuit breaker, not 30 amp.
There is no issue with the tug end of things, just the connection in the van. There is a fuse at each battery.
Had a Projecta 25amp DC-DC charger fitted to caravan.
Solar input works fine, but the ignition feed keeps blowing the 30 amp fuse.
Output from the Alternator is 14.2 volts.
No surpises here, bloke that installed it has ****ed everything he has touched.
In the van wiring?
Blowing fuse 30 amp. in the van. Car wiring checked by Autospark and all good.
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.
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.
I note that the input fuse raring (rating, bit old to be raring fuses
) is 50w
-- Edited by Snippy on Wednesday 29th of August 2018 12:57:38 PM
I have just spoken with Projecta tech support, (Brown and Watson).
The ignition feed fuse should be 50amp circuit breaker. The installer has has used a 30 amp inline fuse on 30amp cable.
I am tempted to name the idiot installer, but softly softly for now.
good call I think.
I have the ID25 in my pajero and I'm pretty sure the instructions called for a 30amp breaker/fuse.
I checked the online install instructions and it says 50amp.
So I'm thinking it may have changed at some point and he may very well have followed the older instruction.
That being said, I used a 30amp and had no issues with it tripping or causing any issues.
Not sure if that helps any
Just be aware that there are two types of cct breakers - auto-resetting & manual resetting - the latter gives you better control of any fault.
I have seen a disastrous issue with an auto where the people involved weren't aware of a problem until they stopped & saw smoke!
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.
The manual he was given said 50w. The bloke is a cowboy. RV Builder in Beaudesert(Ooops slipped out)
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.
Alternator/ battery feed =50amp fuse
Ignition override sense wire [to remotely turn unit on/off ] fused 1-2 amps
Hi Swamp, yes as per the manual, too easy, well for most of us.
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
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
Thanks everyone for your input. Will hook it up tomorrow and let you now how it all goes.
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.
Hi Peter,
(However, if there is a battery at each end of the line you should have a fuse at each battery.)
Yes it is the second battery the one in the van that has the wrong fuse.
Projecta tech support bloke said this needs to be 50 watt amp circuit breaker, not 30 amp.
There is no issue with the tug end of things, just the connection in the van. There is a fuse at each battery.