aftermarket

My Feedback: (2)

Will someone please explain how the threshold settings work?

I've got the 960 and it usually chooses for me, but I accidentally hit the adjust button and now it's always at a single number. How do I make it go back to choosing the threshold by itself? Or is there a rule of thumb on where it should be?

Thanks!

guver

My Feedback: (325)

For NIMH batteries it should be set to 5 mv per cell (multiply number of cells by 5 for the setting) OR power it down and it will start selecting the correct value by itself again.

aftermarket

My Feedback: (2)

It remembers the amps and threshold that I left it at whenever I unplug it... other idea?

guver

My Feedback: (325)

It should default to 5 mv per cell when battery AND power is removed. It may be coincidence that a 6 cell battery is showing 25 or 30 mv on screen. Do you have a different voltage battery you can try?

Is it able to be set manually still?

Tim@MRC

I just found out from my engineer, that there are no more "Factory Defaults" in the 960. Once a setting is made, the charger will retain the last setting. The default was 5 mv per cell. So typically it would be 30mv for a 6 cell battery. This forces you to check your settings for every single battery. Do you need an explaination of what the setting does?

Tim Sandor

guver

My Feedback: (325)

That may be better then to default like mine, it is 1095. Does the current stay at the last set-point too?

Tim@MRC

Yes, the current stays from the last charge. Also, it now adjusts in 0.10 increments, and show the MAH going into the battery.

guver

My Feedback: (325)

very nice feature

aftermarket

My Feedback: (2)

Maybe someone can also explain the delta peak threshold concept?

Thanks!

guver

My Feedback: (325)

See how the voltage climbs up and up until it crests off , after it begins to drop when full it has to drop a certain amount in order to stop the charge. The charger looks for this drop (adjustable amount) to know when to kick off.

The higher the voltage (number of cells) the more drop is required to know when full.

It is a bit more complex , but it could be stated as the "difference between peak voltage and the termination voltage"

It is a very tiny amont of drop and in the 3rd graph you can see the drop or Voltage threshold or delta peak or negative delta peak. It is the difference between y-1 and y-2, looks to be about 140 mv (much higher than the 960 graph in the middle)

Tim@MRC

Love your graphs guver, that is too cool. How do you do that again?

Also, to explain the term "Delta Peak Charger", the word "Delta", is just a fancy way of saying "Change In", so all of the chargers in this class are considered "Change in" Peak chargers, which guvers graphs show very well. The graphs show that as you charge a battery, the voltage is consistently rising. When you reach the point at which the battery is fully charged, you reach a peak voltage. If you keep trying to charge the battery, the battery will actually start to lose a little voltage. It's this small "change in" the peak voltage that the chargers look for to determine when a battery is fully charged. Considering that a millivolt (mv) is one thousandth of a volt, and for NiMH's we use up to 5 mv per cell, in a typical 6 cell battery we look for 30 thousandths of a volt deviation from peak.


Tim Sandor

guver

My Feedback: (325)

Thanks, I use a radio shack DVM that has a rs232 interface for hooking up to pc. It just samples every second and plots it on screen. It could use some more options like measuring in .001 rather than .01 and maybe a sampling rate of less than 1 second and more than 1 minute , but I think it has been discontinued.

First 960 graph shut off with code 05 , the second with code 02, It can definately see the drop with the 960 of 30 mv with no problem. I can't seem to find the normal 01 stop graph. The next graph is an old charger that (in my opinion) allowed too much drop and slightly overcharged. Maybe it is a nicad charger.

Tim@MRC

I checked, Radio Shack still has a DMM w/PC interface - $69.99. Actually, there are quite a few of them out there. I'm going to have to get me one of them. That's a pretty neat "Look what I got"!

Tim

guver

My Feedback: (325)

I use it all the time and is one of the best investents I've made. If you find one with the temp probe included and sampling rate of something more frequent than 1 second or less frequent than 1 minute intervals I'd be interested in getting another.

Some of the small data loggers may be even better and can monitor multiple functions at once.