Is there any chance that a battery maintainer (CTEK 7002) would physically damage an alternator?
Battery Maintainer damage an alternator?
- Thread starter BMWTurboDzl
- Start date
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
No
I use a maintainer all the time on my Jeep. Never a problem. I used to have a nice solar one I used for many years. I am looking for another one like it.
I currently have one mounted atop the battery in the Firebird in my signature for the past 20 years. I've connected it permanently with a longer cord so I don't even have to pop the hood(bonnet) when I plug'er in. And I use another maintainer on the other cars in my signature quite regularly, several times a week.
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Originally Posted by BMWTurboDzl
Is there any chance that a battery maintainer (CTEK 7002) would physically damage an alternator?
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of.
I have thousands of cycles on mine, but Im just one guy....
UD
Is there any chance that a battery maintainer (CTEK 7002) would physically damage an alternator?
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of.
I have thousands of cycles on mine, but Im just one guy....
UD
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Originally Posted by CR94
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Ive connected the charger directly to battery cables before engaging "alternator mode"
That subjected the alternator to whatever max output was.
Done this several times with no issue so I could pull someones batt and try to recover.
UD
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Ive connected the charger directly to battery cables before engaging "alternator mode"
That subjected the alternator to whatever max output was.
Done this several times with no issue so I could pull someones batt and try to recover.
UD
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
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Originally Posted by ripcord
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
Just be careful to not reverse polarity . Do not know if it will damage an alternator , but I have read it can cause havoc with the vehicle electronics .
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
Just be careful to not reverse polarity . Do not know if it will damage an alternator , but I have read it can cause havoc with the vehicle electronics .
Originally Posted by WyrTwister
Originally Posted by ripcord
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
Just be careful to not reverse polarity . Do not know if it will damage an alternator , but I have read it can cause havoc with the vehicle electronics .
The Ctek has polarity detection.
UD
Originally Posted by ripcord
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
Just be careful to not reverse polarity . Do not know if it will damage an alternator , but I have read it can cause havoc with the vehicle electronics .
The Ctek has polarity detection.
UD
Originally Posted by BMWTurboDzl
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
I like that about my sprinter.
My ridgeline is a pain to reach the battery.
UD
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
I like that about my sprinter.
My ridgeline is a pain to reach the battery.
UD
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Originally Posted by ripcord
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
Yes, but as a corollary to that an alternator with an open diode can wreck a battery. In a moment of weakness, I once bought a rebuilt alternator from AZ. My battery would discharge quickly. Took it back, got another, did the same thing, PITA to R&R. Bad diodes in both cases. Warrantied. Insisted on a NEW Denso unit for my time and trouble, they actually agreed. No problems since. 1987 Accord. Great car but soon for sale.
Alternators (functional ones anyway) have a diode that prevents current from flowing from the battery back to the alternator. Think of it as a one way valve. There should be no problem charging a battery with the cables attached. That said, you should check your owners manual to see what it says.
Yes, but as a corollary to that an alternator with an open diode can wreck a battery. In a moment of weakness, I once bought a rebuilt alternator from AZ. My battery would discharge quickly. Took it back, got another, did the same thing, PITA to R&R. Bad diodes in both cases. Warrantied. Insisted on a NEW Denso unit for my time and trouble, they actually agreed. No problems since. 1987 Accord. Great car but soon for sale.
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I have seen a youtube video ( Eric O. ? ) using a scope to detect increased " ripple " due to a defective diode .
No, the alternator has diodes to prevent the reverse flow of current. The diodes will certainly fail if subjected to a high enough voltage, but the 15V or whatever that charger could produce isn't going to do it. Since I bought a house with a garage 2 years ago, I have been plugging my car into my Battery Tender every night with no issues.
The diodes are internal to rectify the 3ph to DC.
An open diode will not discharge the battery. A diode on the +ve will.
Waste of time scope-ing the output of charger when it is not connected.
Scope-ing the output of a running alternator will show if a diode is not functioning as it should.
High voltage can cause a diode to short. Normally its heat that fries them & they go open.
An open diode will not discharge the battery. A diode on the +ve will.
Waste of time scope-ing the output of charger when it is not connected.
Scope-ing the output of a running alternator will show if a diode is not functioning as it should.
High voltage can cause a diode to short. Normally its heat that fries them & they go open.
Originally Posted by CR94
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Originally Posted by BMWTurboDzl
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
Only brands that do that are BMW and mercedes that I'm aware off. Some vans of other brands have the battery in the passenger compartment though.
Some cars have a second battery inside the trunk, seen that on peugeot and mercedes.
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Originally Posted by BMWTurboDzl
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
Only brands that do that are BMW and mercedes that I'm aware off. Some vans of other brands have the battery in the passenger compartment though.
Some cars have a second battery inside the trunk, seen that on peugeot and mercedes.
Originally Posted by Jetronic
Originally Posted by CR94
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Originally Posted by BMWTurboDzl
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
Only brands that do that are BMW and mercedes that I'm aware off. Some vans of other brands have the battery in the passenger compartment though.
A lot of brands do that. My Dodge Stratus has the battery in the wheel well in the bumper and has positive and negative terminals under the hood, my friend's Cadillac CTS has the battery in the trunk with a positive terminal under the hood, and my mom's Volvo XC70 had the battery in the back and had terminals under the hood to jump it if I remember correctly.
Originally Posted by CR94
Originally Posted by UncleDave
Dont see how unless it was damaged maybe - but it would kill your battery if that were the case - and it would be a first Ive heard of. ...
What if, while the charger is connected across the vehicle's battery cables, the cables somehow lose contact with a battery terminal? Then the battery can no longer act as a buffer or capacitor to protect the the vehicle electrical system from any spikes in the charger output. I assume that's probably not a problem with most chargers, but can we be certain, without checking the charger's open-circuit output with an oscilloscope?
Originally Posted by BMWTurboDzl
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
Only brands that do that are BMW and mercedes that I'm aware off. Some vans of other brands have the battery in the passenger compartment though.
A lot of brands do that. My Dodge Stratus has the battery in the wheel well in the bumper and has positive and negative terminals under the hood, my friend's Cadillac CTS has the battery in the trunk with a positive terminal under the hood, and my mom's Volvo XC70 had the battery in the back and had terminals under the hood to jump it if I remember correctly.
JHZR2
Staff member
Originally Posted by BMWTurboDzl
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
I've had an SAE plug connected (with fuse) to that jumping lug underhood in my 135i for years. No issues whatsoever.
Thanks gents. I didn't think so, but I had to ask because I was in serious trouble if it caused my alternator to crap out.
For the record on many if not all euro cars today there's a positive terminal in the engine bay and a grounding stud attached to the body. Battery is typically located in the trunk or seat. You use these connectors when jumping the car and when using a battery tender.
I've had an SAE plug connected (with fuse) to that jumping lug underhood in my 135i for years. No issues whatsoever.