 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
kenryan
Joined: 20 Oct 2009
Posts: 426
|
 Posted: Sat Sep 09, 2017 8:22 am Post subject: Alternators - To Fuse or not to fuse - That IS the question |
 |
|
A few weeks (?) ago, Bob posted a link to a Harbor Freight 500 Amp Carbon Pile Load Tester:
https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html
I thought that this is what we would use to annually test the capacity of our batteries. I thought that we would connect the battery, set the amps to our expected load (for example, 12 amps) and then time how long until battery voltage reaches an unacceptably low level.
But, upon reviewing the user manual for this tool, it does not look like that is what this thing is for. It appears to just load the battery for a short period of time and then extrapolate the battery condition based on how it behaves for that very short test period.
What's the deal? How do we use this tool to check on our battery condition, annually?
Ken
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
 |
donvansanten(at)gmail.com
Guest
|
| Posted: Sat Sep 09, 2017 8:44 am Post subject: Alternators - To Fuse or not to fuse - That IS the question |
|
|
Ken,The device tbat would test the battery the way you thought is a West Mountain CBA. The carbon pile is set at a much higher amp rate and draws the battery down very fast. You still get capacity by comparing amps extracted per unit of time.
On Sep 9, 2017 09:26, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | A few weeks (?) ago, Bob posted a link to a Harbor Freight 500 Amp Carbon Pile Load Tester:
https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html
I thought that this is what we would use to annually test the capacity of our batteries. I thought that we would connect the battery, set the amps to our expected load (for example, 12 amps) and then time how long until battery voltage reaches an unacceptably low level.
But, upon reviewing the user manual for this tool, it does not look like that is what this thing is for. It appears to just load the battery for a short period of time and then extrapolate the battery condition based on how it behaves for that very short test period.
What's the deal? How do we use this tool to check on our battery condition, annually?
Ken
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
kenryan
Joined: 20 Oct 2009
Posts: 426
|
| Posted: Sat Sep 09, 2017 9:38 am Post subject: Alternators - To Fuse or not to fuse - That IS the question |
|
|
Don,Thanks for the West Mountain CBA info. One possible problem I see with using the carbon pile is that the algorithms used to derive capacity are probably based on lead acid batteries, not LiFePO batteries. Aren't the discharge characteristics of Li batteries radically different from lead acid batteries?
Ken
On Sat, Sep 9, 2017 at 8:42 AM, don van santen <donvansanten(at)gmail.com (donvansanten(at)gmail.com)> wrote:
| Quote: | Ken,The device tbat would test the battery the way you thought is a West Mountain CBA. The carbon pile is set at a much higher amp rate and draws the battery down very fast. You still get capacity by comparing amps extracted per unit of time.
On Sep 9, 2017 09:26, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | A few weeks (?) ago, Bob posted a link to a Harbor Freight 500 Amp Carbon Pile Load Tester:
https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html
I thought that this is what we would use to annually test the capacity of our batteries. I thought that we would connect the battery, set the amps to our expected load (for example, 12 amps) and then time how long until battery voltage reaches an unacceptably low level.
But, upon reviewing the user manual for this tool, it does not look like that is what this thing is for. It appears to just load the battery for a short period of time and then extrapolate the battery condition based on how it behaves for that very short test period.
What's the deal? How do we use this tool to check on our battery condition, annually?
Ken
|
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
donvansanten(at)gmail.com
Guest
|
| Posted: Sat Sep 09, 2017 10:22 am Post subject: Alternators - To Fuse or not to fuse - That IS the question |
|
|
The discharge characteristics are not dirrerent enough to cause a problem using the carbon pile. If you try the pile be careful, they get quite hot. I prefer to use the CBA, but it takes many hours to discharge to 10 volts.
On Sep 9, 2017 10:42 AM, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | Don,Thanks for the West Mountain CBA info. One possible problem I see with using the carbon pile is that the algorithms used to derive capacity are probably based on lead acid batteries, not LiFePO batteries. Aren't the discharge characteristics of Li batteries radically different from lead acid batteries?
Ken
On Sat, Sep 9, 2017 at 8:42 AM, don van santen <donvansanten(at)gmail.com (donvansanten(at)gmail.com)> wrote:
| Quote: | Ken,The device tbat would test the battery the way you thought is a West Mountain CBA. The carbon pile is set at a much higher amp rate and draws the battery down very fast. You still get capacity by comparing amps extracted per unit of time.
On Sep 9, 2017 09:26, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | A few weeks (?) ago, Bob posted a link to a Harbor Freight 500 Amp Carbon Pile Load Tester:
https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html
I thought that this is what we would use to annually test the capacity of our batteries. I thought that we would connect the battery, set the amps to our expected load (for example, 12 amps) and then time how long until battery voltage reaches an unacceptably low level.
But, upon reviewing the user manual for this tool, it does not look like that is what this thing is for. It appears to just load the battery for a short period of time and then extrapolate the battery condition based on how it behaves for that very short test period.
What's the deal? How do we use this tool to check on our battery condition, annually?
Ken
|
|
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
ceengland7(at)gmail.com
Guest
|
| Posted: Sat Sep 09, 2017 12:24 pm Post subject: Alternators - To Fuse or not to fuse - That IS the question |
|
|
Well, an single SLA has very different amp-hour ratings depending on the discharge rate. And 'consumer' SLAs (PC680, etc that were originally intended for watercraft, and others that some of us use that were intended for UPSs and/or electric carts, etc) are rated differently from the certified a/c SLAs, if I've read spec sheets correctly.
The most common LiFePO discussed here claims to maintain its rated AH output at the AH number for one hour. The consumer SLAs most of us are using won't do that; they'll only go for about 40% of their rating if loaded to the max. Some of the early offerings for starting batteries using lithium chemistry wouldn't go for more than a few minutes at their full labeled rating.
But maybe if all are only loaded for a small number of seconds, you can still derive useful info. Is that really the case?
On Sat, Sep 9, 2017 at 1:21 PM, don van santen <donvansanten(at)gmail.com (donvansanten(at)gmail.com)> wrote:
| Quote: | The discharge characteristics are not dirrerent enough to cause a problem using the carbon pile. If you try the pile be careful, they get quite hot. I prefer to use the CBA, but it takes many hours to discharge to 10 volts.
On Sep 9, 2017 10:42 AM, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | Don,Thanks for the West Mountain CBA info. One possible problem I see with using the carbon pile is that the algorithms used to derive capacity are probably based on lead acid batteries, not LiFePO batteries. Aren't the discharge characteristics of Li batteries radically different from lead acid batteries?
Ken
On Sat, Sep 9, 2017 at 8:42 AM, don van santen <donvansanten(at)gmail.com (donvansanten(at)gmail.com)> wrote:
| Quote: | Ken,The device tbat would test the battery the way you thought is a West Mountain CBA. The carbon pile is set at a much higher amp rate and draws the battery down very fast. You still get capacity by comparing amps extracted per unit of time.
On Sep 9, 2017 09:26, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | A few weeks (?) ago, Bob posted a link to a Harbor Freight 500 Amp Carbon Pile Load Tester:
https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html
I thought that this is what we would use to annually test the capacity of our batteries. I thought that we would connect the battery, set the amps to our expected load (for example, 12 amps) and then time how long until battery voltage reaches an unacceptably low level.
But, upon reviewing the user manual for this tool, it does not look like that is what this thing is for. It appears to just load the battery for a short period of time and then extrapolate the battery condition based on how it behaves for that very short test period.
What's the deal? How do we use this tool to check on our battery condition, annually?
Ken
|
|
|
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
donvansanten(at)gmail.com
Guest
|
| Posted: Sat Sep 09, 2017 12:54 pm Post subject: Alternators - To Fuse or not to fuse - That IS the question |
|
|
The first test (new batt) is the baseline. Latter tests let you see performance dropoff. So yes you an obtain useful information even though the device dors not perfectly match the batteries discharge characteristics. Again, I prefer the West Mountain CBA, even if it takes 10 hours per test.
On Sep 9, 2017 13:29, "Charlie England" <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote: | Quote: | Well, an single SLA has very different amp-hour ratings depending on the discharge rate. And 'consumer' SLAs (PC680, etc that were originally intended for watercraft, and others that some of us use that were intended for UPSs and/or electric carts, etc) are rated differently from the certified a/c SLAs, if I've read spec sheets correctly.
The most common LiFePO discussed here claims to maintain its rated AH output at the AH number for one hour. The consumer SLAs most of us are using won't do that; they'll only go for about 40% of their rating if loaded to the max. Some of the early offerings for starting batteries using lithium chemistry wouldn't go for more than a few minutes at their full labeled rating.
But maybe if all are only loaded for a small number of seconds, you can still derive useful info. Is that really the case?
On Sat, Sep 9, 2017 at 1:21 PM, don van santen <donvansanten(at)gmail.com (donvansanten(at)gmail.com)> wrote:
| Quote: | The discharge characteristics are not dirrerent enough to cause a problem using the carbon pile. If you try the pile be careful, they get quite hot. I prefer to use the CBA, but it takes many hours to discharge to 10 volts.
On Sep 9, 2017 10:42 AM, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | Don,Thanks for the West Mountain CBA info. One possible problem I see with using the carbon pile is that the algorithms used to derive capacity are probably based on lead acid batteries, not LiFePO batteries. Aren't the discharge characteristics of Li batteries radically different from lead acid batteries?
Ken
On Sat, Sep 9, 2017 at 8:42 AM, don van santen <donvansanten(at)gmail.com (donvansanten(at)gmail.com)> wrote:
| Quote: | Ken,The device tbat would test the battery the way you thought is a West Mountain CBA. The carbon pile is set at a much higher amp rate and draws the battery down very fast. You still get capacity by comparing amps extracted per unit of time.
On Sep 9, 2017 09:26, "Ken Ryan" <keninalaska(at)gmail.com (keninalaska(at)gmail.com)> wrote: | Quote: | A few weeks (?) ago, Bob posted a link to a Harbor Freight 500 Amp Carbon Pile Load Tester:
https://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html
I thought that this is what we would use to annually test the capacity of our batteries. I thought that we would connect the battery, set the amps to our expected load (for example, 12 amps) and then time how long until battery voltage reaches an unacceptably low level.
But, upon reviewing the user manual for this tool, it does not look like that is what this thing is for. It appears to just load the battery for a short period of time and then extrapolate the battery condition based on how it behaves for that very short test period.
What's the deal? How do we use this tool to check on our battery condition, annually?
Ken
|
|
|
|
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
