I have a KX-T61610, version 3, that has no battery or pigtail visible. I haven't popped the cover off to see if the pigtail just got pushed back inside or something. Did any of these not come with a battery? I've got the programing set perfect, and I don't feel like doing it all over again.
They all come with a battery as far as I know. Perhaps someone took the cover off and did not thread the battery pigtail back into the battery area before putting the cover back on. I would take the cover off and look.
This is the connector on a replacement battery I picked up last year.
(http://www.classicrotaryphones.com/forum/index.php?action=dlattach;topic=13471.0;attach=115127;image)
It's black but the correct connector for the female on the pigtail in my 616, which is white. I only have one 616 so maybe they came in other colors. But as Phonesrfun said, they all came with a battery.
The cost of the correct replacement battery (the right size with the right connector) was about $12 plus shipping. There are several discussion of 616 batteries, here is one link.
http://www.classicrotaryphones.com/forum/index.php?topic=13471.msg141312#msg141312
Has it been directly attached to the PCB inside the unit perhaps?
Thanks guys. Price is pretty reasonable, so I got one coming. It may be a while until I get a chance to pop it open.
I received my battery today. I popped the cover off and I cannot for the life of me find the pigtail. What am I missing?
Could you take a picture of the inside of the unit? It's either been tucked inside the case or it's been modernised with a PCB-mounded battery...
Here's the inside. I lifted the top board up enough to see underneath. I looked for another battery of some type and I didn't see anything.
Here's another pic and the tag. Not sure if it is a late production model? 11/98 is hand written on the inside of the cover. Not sure if that was when it was taken out of service or a refurbished or service date.
If there's a connection or replacement for the battery in there, it'd be on the board underneath....
Quote from: podor on September 19, 2015, 06:39:05 PM
Here's another pic and the tag. Not sure if it is a late production model? 11/98 is hand written on the inside of the cover. Not sure if that was when it was taken out of service or a refurbished or service date.
I am not sure this model line was made anymore in 1998. But in any case, the battery connects to a red/black wire pair terminated in the lower main circuit board. It should have emerged somewhere by the gray ribbon cable.
The top circuit board contains primarily the station line interface circuits, the power fail relays, and the jacks. The lower board contains the processor and the cross point switch.
Since you got this far, popping out the top board is not too hard.
Here is a picture of the lower main board of a version 3 unit.
You can see the black/red pair on the left-hand side.
Well, there is a CR2354 mounted to the board instead (wrapped in yellow). Mystery solved. Anyone need a battery? I'll try to post pictures later. I keep getting the security error.
Was this installed in the factory?
The CR2354 is not rechargeable, so it will eventually run out too.
I thought you were looking for the battery because your unit did not hold the configuration.
PS: try resizing your picture by 1 pixel or so.
The connector on the rechargeable battery is a male JST-SMP-02N (N for neutral or white, also come in B for black)
The pigtail on the 616 has a female JST-SMR-02N (same as the -02B) in case you want to and are able to add the pigtail to reach the battery compartment.
JST is the manufacturer (Japan Solderless Terminals), SMR-02 is the two conductor connector. Problem is finding one in small quantity at a reasonable price (minimum order problems with a 10 cent connector) that already has the pins wired in.
Or just replace the battery connector to whatever works for you.
It appears to be factory. I haven't had any memory issues yet, I just want to make sure I don't lose my program. It's pretty elaborate. Would it keep the battery charged if I installed the pigtail?
unbeldi, what about the voltage difference. The KX-A16 is a 2.4 volt NiCd rechargeable while the CR 2354 3v Lithium Ion battery.
Could there be a resistor in the PC circuit to compensate or is +0.6 volts not that big of a deal.
Quote from: TelePlay on September 19, 2015, 09:32:12 PM
unbeldi, what about the voltage difference. The KX-A16 is a 2.4 volt NiCd rechargeable while the CR 2354 3v Lithium Ion battery.
Could there be a resistor in the PC circuit to compensate or is +0.6 volts not that big of a deal.
I was concerned about the voltage difference too before I saw the picture. But they took out the large 2200 µF capacitor as well. I can't tell from the picture exactly whether the circuit traces are still there or whether they redesigned the whole battery feed.
The CR2354 also has higher capacity (>500 mAh vs 110 mAh).
I'll just grab a replacement. No big deal. I'm not too worried about my $12 investment on the other battery. I've spent way more $ on the wrong part before. Thanks for everyone's help!
Comparing the two boards as best as I could given the photos do no quite match, it seems the CR 2354 has a much larger diameter than the capacitor that was removed and as such covers up components - the battery covers what is about in the yellow circle in the photo on the right.
Also, the CR 2354 is a thin battery and what I see is a CR 2354 in a yellow holder of sorts that is very thick. So, could it be a special battery holder which raises the thin CR 2354 up above the board components?
If so, is the battery holder for the CR 2354 a screw down bracket because if there are components under the battery, that would not allow it to be slid out sideways.
Curious issue.
Quote from: TelePlay on September 19, 2015, 10:21:26 PM
Comparing the two boards as best as I could given the photos do no quite match, it seems the CR 2354 has a much larger diameter than the capacitor that was removed and as such covers up components - the battery covers what is about in the yellow circle in the photo on the right.
Also, the CR 2354 is a thin battery and what I see is a CR 2354 in a yellow holder of sorts that is very thick. So, could it be a special battery holder which raises the thin CR 2354 up above the board components?
If so, is the battery holder for the CR 2354 a screw down bracket because if there are components under the battery, that would not allow it to be slid out sideways.
Curious issue.
The battery doesn't have a holder, actually, I think. The terminals are spot-welded on the top and bottom, and are designed to insert into holes on the PCB for soldering. The yellow material is simply insulation shrink-wrap, just like the green plastic around the large cap next to it. As for space, it could easily be elevated over and cover up the few small components surrounding the original wire points. [added: However, the bracket could still be some kind of holder, I suppose, which simply clamps the cell between two metal contacts.
That big capacitor, btw, has a size of 1 farad, perhaps a supercap of the 1980s, and I have not figured out its function, I haven't actually even found it in the circuit diagrams, but I haven't been looking at that detail very much. It may serve as backup power source in case the battery is exchanged during power off.
The static RAM that is powered by the battery when utility power is off has an operating voltage of 5 V, but for only holding data the voltage is permissible to go to 2 V, according to the data sheet. So, while I haven't taken any measurements of the battery circuit, it may mean that the potential of the battery is not so important as long as it has a safety margin above 2 V.
Next time I open one of my units, I might take some measurements on the battery feed. This discussion may have been very useful, because in case of failure I could replace the expensive original battery with a much cheaper, more readily available type, such as the one in this board.
Quote from: unbeldi on September 20, 2015, 10:38:28 AM
The battery doesn't have a holder, actually, I think. The terminals are spot-welded on the top and bottom, and are designed to insert into holes on the PCB for soldering. The yellow material is simply insulation shrink-wrap, just like the green plastic around the large cap next to it. As for space, it could easily be elevated over and cover up the few small components surrounding the original wire points. [added: However, the bracket could still be some kind of holder, I suppose, which simply clamps the cell between two metal contacts.
podor,
Could you take a photo of the battery from the top down, similar to unbeldi's full board original image (I can crop it for a comparison) and a close-up of the battery from the other side showing how the holder wraps down around the battery and attaches to the board?
Thanks.
Sure. I'll take some more detailed pictures when I replace the battery. It's back in service for the time being.
Is the battery used when the power switch is off, or is it just for power failure? Sometimes, for my wife's sake, it's easier to switch it off when the kids get a little carried away ringing each other.
I was also wondering if the circuit diagrams are published. I would like to be able to troubleshoot in the future.
From what I've read, I think the battery saves the memory when the unit has a power failure or it is unplugged. One of the way other members boot it back to factory setting is to unplug the unit and disconnect the battery for some period of time allowing caps to discharge and the memory to go blank, forcing the unit back to factory settings on the next power up, all programming lost.
Good question about turning off the power switch vs totally unplugging the unit. unbeldi should be able to answer that question after looking at the schematics in the power circuit.
Quote from: TelePlay on September 20, 2015, 04:25:30 PM
From what I've read, I think the battery saves the memory when the unit has a power failure or it is unplugged. One of the way other members boot it back to factory setting is to unplug the unit and disconnect the battery for some period of time allowing caps to discharge and the memory to go blank, forcing the unit back to factory settings on the next power up, all programming lost.
Good question about turning off the power switch vs totally unplugging the unit. unbeldi should be able to answer that question after looking at the schematics in the power circuit.
As I mentioned earlier, the battery powers the static RAM, which stores the configuration and probably other things. It does not matter whether the power is turned off, or has failed, or the unit is unplugged. You want to save the configuration in any case.
Quote from: unbeldi on September 20, 2015, 07:03:30 PM
As I mentioned earlier, the battery powers the static RAM, which stores the configuration and probably other things. It does not matter whether the power is turned off, or has failed, or the unit is unplugged. You want to save the configuration in any case.
I think what he, or I, was asking is if the unit is plugged into the wall and its power switch turned off, will the RAM continue to be preserved by the power cord still plugged into the wall or does the battery start holding the RAM memory as soon as the switch is turned off?
In other words, if a 616 does not have a battery, or the battery is dead, will turning the 616 power switch off kill the RAM memory or will the memory be maintained somehow by the line cord plugged into a hot outlet?
When the power is off, it's off, as the main switch is cutting off mains power to the transformer, the battery is there to hold the settings in volatile memory (I.E. cut power and it loses data), just like in a computer, you have a BIOS battery to retain the settings while the computer is powered off... :)
The supercap that's next to the battery connection I would presume is in-circuit with the battery and holds the settings for a few minutes in the event of a duff battery and intermittent power disruptions, or for retaining the settings while changing the battery with the unit powered off, I've observed this with my 308, which lacks a battery, where turning it off for a couple of minutes and back on again, the system has retained it's settings, but after 10 minutes or so, it's lost them and is back to defaults...
Well, Batteries Plus didn't have the battery, but I've got one coming. To be continued.......
I got the battery today and pulled everything apart again. The battery is permanently mounted. I can barely see underneath with a mirror. It looks like the bottom tab is soldered on to the battery and directly to the board. The top tab looks like it is soldered also, with a bit coming out of the 4 holes in the center. It's then soldered into two points on the board. There are no components underneath the battery as far as I can see. I'm just going to leave it alone. I've wasted enough time and money just so I don't have to reprogram if we loose power, which doesn't really happen that often anyway.
Thanks for the update. Wise decision.
I suspected that the bracket is spot welded to the battery, this is pretty common actually. It was probably installed in the factory or a Panasonic dealer/service center. I will compare with the new picture, thanks.
So I take it you have never powered it down since you configured it?
For posterity, here is the comparison . . .
So, is that a lifetime battery? The battery is expected to outlive the 616? That doesn't seem right being a battery that does not recharge and being in circuit 24/7 from installation. Any thoughts?
Quote from: TelePlay on September 25, 2015, 10:09:10 PM
For posterity, here is the comparison . . .
So, is that a lifetime battery? The battery is expected to outlive the 616? That doesn't seem right being a battery that does not recharge and being in circuit 24/7 from installation. Any thoughts?
It's been done routinely in PCs and other equipment. They consider this is not a field-maintenance task.
This type of battery is 5-times higher in capacity, and considering that some of my batteries appear original and still work, means it takes a very long time to exhaust them. Every piece of equipment has a design lifetime.
Perhaps they also changed the type SRAM in this new design, that requires even less standby current.
The board is definitely redesigned, as we see from your side-by-side comparison.
Actually I have. I turned it off for about an hour. Long story short, some friends' kids were driving my wife crazy with all the rining. It never occurred to me to see if anything was stored from the previous owner. I think it was in the stock programing when I got it. I set the time before I got the programing phone, so it was correct when I stared with the rest of the programing.
Just an update, we have lost power about 4 times since this was discussed and the unit retained its memory. The longest was about 3 hours.