Matronics Email Lists :: View topic - Schumacher for battery maintenance, vote now!

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Schumacher for battery maintenance, vote now!

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

Radioflyer

Joined: 04 Feb 2009
Posts: 43
Location: Boston

Posted: Thu Mar 18, 2010 6:01 am Post subject: Re: Schumacher for battery maintenance, vote now!

Well, what I did was to measure the voltages at the battery terminal with the Schumacher powered on and attached. With the yellow light on, the voltage was 15.6 or thereabouts. When the green light came on, the voltage was very slowly oscillating from 14.6 to just over 15. The battery has sat overnight, unattached to anything and it is now at 12.86V.



Did I measure incorrectly? Is not 14.6 charge/13.2 float ideal and what I should expect from a maintainer?



--Jose

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Mar 18, 2010 6:32 am Post subject: Schumacher for battery maintenance, vote now!

At 08:11 AM 3/18/2010, you wrote:

 	  Quote: 	
		  



After several postings here about how this is the best no-nonsense 

maintainer for Pb-acid chemistry I got myself one from Walmart. 

Model SEM 1562A. I put it on an Odyssey PC625 and checked the 

voltages. The unit was charging at 15.6V. After 3 hrs, the float 

charge kicked in, hovering around 14.6 volts. Later I believe I 

found a review on Amazon from somebody who measured about the same voltages.



What I wanted was 14.6 charge/13.2 float since that was what was 

reported in this forum as correct for the chemistry and for this 

unit. I think the original units came with a 12/6V switch. This unit 

(same model number) has a 12/6V automatic function with no switch. 

It seems the switch is not the only thing that has changed.



I'm returning the unit and now will search for something else. Any 

suggestions?


	


   Are you sure the "float" voltage you were measuring wasn't

   being supported by the battery as opposed to the Schumacher

   maintainer? I have several of the 1562 and they perform

   as expected. After a battery is freshly charged, it may take

   some time for its terminal voltage to drop down to maintenance

   levels with NO charger attached.



   Repeat the experiment but as soon as the charger shuts down

   (drops below the 15.6 top-off), disconnect the charger and

   watch the battery's open circuit terminal voltage. It might

   take several hours for the battery to drop down to the level

   at which the maintainer begins to support it.



   Schumacher has been in this business a very long time. It

   seems unlikely that they've produced a device that fails

   to perform by design. Of course a defective device is anohter

   matter.

   Bob . . .

Radioflyer

Joined: 04 Feb 2009
Posts: 43
Location: Boston

Posted: Thu Mar 18, 2010 8:20 am Post subject: Re: Schumacher for battery maintenance, vote now!

I spoke to Alex at Schumacher technical support. He said this model is no longer available with the manual 12/6 volt switch. The design has changed. The unit is now microprocessor controlled and now only comes with the automatic 12/6V feature. He said the voltages for the new version are set somewhat higher than the older version because the microprocessor can monitor the levels better. He also said that the float voltages I reported are normal, initially due to a high recent charge on the battery, but that it will eventually settle to not more than 13.4V. I think this is what you were also saying.



So, I put the battery back on the charger. The voltage started at 14.6V and within 5 minutes went up to 15.2V. An hour later it was at 15.2V and still charging, yellow light on. I will wait until a few hours after float to see what the float level is then.



If results seem suspicious after this test. I may take you up on your offer, thanks.



--Jose

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Mar 18, 2010 8:22 am Post subject: Schumacher for battery maintenance, vote now!

At 09:01 AM 3/18/2010, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "Radioflyer" <skyeyecorp(at)airpost.net>



 Well, what I did was to measure the voltages at the battery terminal with the Schumacher powered on and attached. With the yellow light on, the voltage was 15.6 or thereabouts. When the green light came on, the voltage was very slowly oscillating from 14.6 to just over 15. The battery has sat overnight, unattached to anything and it is now at 12.86V.



 Did I measure incorrectly? Is not 14.6 charge/13.2 float ideal and what I should expect from a maintainer? 	


    Sounds like you did good. I'd like to have that

    maintainer to evaluate. I've got several 1562's

    and they don't behave that way. I'd like to know

    if Schumacher has changed the design or that one

    is bad.



    As far as a replacement, I also have several Battery

    Tender Juniors that have been keeping my lab batteries

    alive and well for years.



  http://aeroelectric.com/Pictures/Battery_Chargers/Battery_Tender_Jr/Battery_Tender-Junior.jpeg

 

  http://tinyurl.com/yjhhgra 



    If you'll send me your 1562, I'll ship it back when I'm

    done with it and pay postage both ways. See front page

    of website for shipping address.



    Bob . . .

     [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Mar 18, 2010 11:48 am Post subject: Schumacher for battery maintenance, vote now!

 	  Quote: 	
		  

So, I put the battery back on the charger. The voltage started at 

14.6V and within 5 minutes went up to 15.2V. An hour later it was at 

15.2V and still charging, yellow light on. I will wait until a few 

hours after float to see what the float level is then.



If results seem suspicious after this test. I may take you up on 

your offer, thanks.


	


   Give it even a day or so. It should settle down

   to 13.5 or less.



   Bob . . .

pwmac(at)sisna.com
Guest

Posted: Thu Mar 18, 2010 11:04 pm Post subject: Schumacher for battery maintenance, vote now!

I have 4 of those maintainers.  Use on one flooded and the rest are 

AGM. I have never seen more that 14.1 at the batt terminals with the 

thing connected. The batts spend most of the time at 13.1.

Suggest you get a proper meter and measure again. I went thru two 

Radio Shack meters before buying a good meter. Turns out teh Harbor 

Freight 3.99 one is as good as you will get for a batter volt meter. 

Your experience may differ?

PW

==========

At 06:11 AM 3/18/2010, Radioflyer wrote:

 	  Quote: 	
		  



After several postings here about how this is the best no-nonsense 

maintainer for Pb-acid chemistry I got myself one from Walmart. 

Model SEM 1562A. I put it on an Odyssey PC625 and checked the 

voltages. The unit was charging at 15.6V. After 3 hrs, the float 

charge kicked in, hovering around 14.6 volts. Later I believe I 

found a review on Amazon from somebody who measured about the same voltages.



What I wanted was 14.6 charge/13.2 float since that was what was 

reported in this forum as correct for the chemistry and for this 

unit. I think the original units came with a 12/6V switch. This unit 

(same model number) has a 12/6V automatic function with no switch. 

It seems the switch is not the only thing that has changed.



I'm returning the unit and now will search for something else. Any 

suggestions?

--Jose

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Mar 22, 2010 7:08 am Post subject: Schumacher for battery maintenance, vote now!

At 09:09 PM 3/21/2010, you wrote:

 	  Quote: 	
		  



Ok, Bob, you suggested that I monitor the battery over a few days. 

Here is the summary of the Schumacher SEM-1562A voltages across my 

AGM battery(Odyssey PC625). (The battery had been already (night 

prior) charged/maintain by the same device.)



Day 1 - The unit started at 14.6V (yellow light on) and quickly 

ramped up to 15.2V. About 1.5hr later, the float commenced (green 

light on). The Voltages ranged (sinusoidally?) from 13.6 to 15.3V 

over about a 20 second period.



Day 2 - (24hrs later) The unit was still ranging thru 13.6 to 15.2V.



Day 3 - The unit ranged from 13.7 to 15.8V, but there was more 

loiter time nearer the 13.7V end. 12 hrs later in the day (or maybe 

less) the unit had stabilized at 13.7V



Day 4 - Values continue to be stable at 13.7V with no indication of 

any further change. I then disconnected the Schumacher and 

terminated measurements.



The Schumacher started with a brief topping off voltage of 15.2V, 

continued with a long float of 13.6 to 15.2V averaging to about 

14.4V, and finally settled on a constant 13.7V. The volatges seems 

high to me. The manual states max charge of 14.6V, maintainance 

13.3V, but I don't know if these are "averaged" values. So, is this 

optimal or reasonable behavior for maintaining my battery? Clearly, 

this new version of the SEM-1562A is operating quite differently 

from the original version.


	


   Thank you for taking the time to accomplish this study!

   My data acquisition system is still packed up in moving

   boxes but as soon as I can get some more pressing matters

   addressed, I'll go pick up another 1562 and see what I

   find. Clearly, the item you have behaves much like some

   very old versions of electronically controlled charger-

   maintainers. In fact, I think I'd like to buy the one

   you have in hand and take it apart to compare with

   others I have and one that I'll buy.



   Let's make a deal.



   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Mar 22, 2010 10:47 am Post subject: Schumacher for battery maintenance, vote now!

At 01:22 PM 3/22/2010, you wrote:

 	  Quote: 	
		  



And I think the original version of the Schumacher SEM-1562A had 

adjustment trimpots also. However, this new version of the same 

model is microprocessor controlled and has no trimpots. The voltages 

must be controlled by firmware.


	


   Have you had it open? Certainly if I were designing

   one, it would indeed have a micro-controller with the

   calibration established by a couple precision resistors

   and the processor's 10-bit a/d. Given that its so

   very easy to do, I'm mystified as to why anyone would

   not do it.



   But the voltages and behaviors you cited are waaayyy out

   of whack.



   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Mar 22, 2010 11:18 am Post subject: Schumacher for battery maintenance, vote now!

At 11:21 AM 3/22/2010, you wrote:




Wondering, if these products are coming out of China or some other 

mass producing factory where the final calibration "station" to set 

the peak charge and float voltages pots is poorly set-up or 

non-existent.  I have used the BatteryMinder model 12117; the small 

unit.  I like it.



    <snip>



Conclusion.... many products of good designs like this one are 

leaving the factories with thinly disguised Q/C



    Fooey. It's entirely possible. I guess I'll have

    to start checking any new ones I buy. It wouldn't

    take much to fabricate a battery maintainer module

    to be powered by any orphaned wall-wart. Most

    of the 12v unregulated devices put out enough

    voltage at light loads to top-off an svla battery.



    A simple circuit to drop from a 14.8 top-off to

    13.2  maintenance when top-off current drops

    under 100 ma wouldn't be very hard to do . . .

    even as an discrete analog circuit.  Don't

    need any more projects right now. I'm still

    building desks and cabinets!



        Bob . . .

                    ////

                   (o o)

    ===========o00o=(_)=o00o=========

    < Go ahead, make my day . . .   >

    < show me where I'm wrong.      >

    =================================

Radioflyer

Joined: 04 Feb 2009
Posts: 43
Location: Boston

Posted: Mon Mar 22, 2010 11:51 am Post subject: Re: Schumacher for battery maintenance, vote now!

Yes, I did open the unit immediately after realizing the voltages were higher than expected. Since no trimpots, I closed it up to return to the store for a refund. Then based on our discussions here, I decided to test it a little longer. 



I probably should return it but if you (Bob N.) are interested, I could certainly send it to you for further testing. 



Bob N.,  I'll try contacting you off list to send you the unit.



--Jose

trumanst(at)neitel.net
Guest

Posted: Mon Mar 22, 2010 2:14 pm Post subject: Schumacher for battery maintenance, vote now!

Bob,

I too have a new version of the Schumacher. I have not tried the voltage checks, but did notice that it took substantially longer for the new unit to top off my PC 680. Compared to the older unit. The old unit would sometimes go into float in a minute or less.

The new unit was charging for half an hour or longer. I did close the alternate buss feed to check volts on the panel. If I remember correctly the panel voltmeter was well in excess of 14 nearing 15 volts. That reading is less that accurate as the graduations on my voltmeter are 9,12,15 etc. Bottom line is that I too felt there was quite a change from the old model to the new one.

Kevin Boddicker

TriQ 200 N7868B   160.4 hrs

Luana, IA.

On Mar 22, 2010, at 1:45 PM, Robert L. Nuckolls, III wrote:

 	  Quote: 	

 At 01:22 PM 3/22/2010, you wrote:

> 

> 

> And I think the original version of the Schumacher SEM-1562A had adjustment trimpots also. However, this new version of the same model is microprocessor controlled and has no trimpots. The voltages must be controlled by firmware.

  Have you had it open? Certainly if I were designing

  one, it would indeed have a micro-controller with the

  calibration established by a couple precision resistors

  and the processor's 10-bit a/d. Given that its so

  very easy to do, I'm mystified as to why anyone would

  not do it.

  But the voltages and behaviors you cited are waaayyy out

  of whack.

  Bob . . .

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

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