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JRDG Coherence II; Battery Display Issue

We had a power outage here in New York that lasted 3 days. I shut down the system, but didn't think to power down the CII. It is operating fine, but neither the LOW or FULL light is illuminated for the battery. The power came back on Tuesday at about midnight, so its been receiving AC for nearly 40+ hours. Does this mean the battery is no longer holding a full charge? Will it affect performance? Frankly, I didn't notice whether the light was illuminated before the power outage

Three additional details. When I power down the PS, it automatically powers up within about 5 seconds. Also, the FULL lamp comes on for a second then goes off. This at least tells me the lamp is functioning. Lastly, when I switch from AC to Battery, there is no discernible fall off in performance. Basically, everything seems to be working, but the LOW/FULL lamps are dark.
128x128stew3859
guidocorona
4,298 posts
 
There are 2 JRDG-authorized repair shops in New York State. They are both listed on the JRDG Knowledge base at:

http://jeffrowlandgroup.com/kb/questions.php?questionid=483
stew3859's avatar
stew3859 OP
119 posts
 
Looks like battery is shot. I switched mode over to battery and it autromatically cycled back inside of 2 hours. As much as I dread it, I will have to bite the bullet and swap out the batteries for new ones. I was told to remove the unit completely from all power sources and let it sit for a couple of hours, if not overnight. This will let the circuit reset.
guidocorona
4,298 posts
 
Uck.... Looks like the 3 days long battery drain zeroed the battery and possibly inverted their polarity as well. Remember to apply a touch of vaseline or similar lubricant onto the walls of the battery compartment, to prevent the fresh set from ever getting stuck inside. There is a specific JRDG bulletin, which states....

"placement Battery Installation

The replacement batteries for the Coherence and Coherence II preamplifiers are chosen specifically to fit into the holes cut into the preamplifier power supply chassis.

To install the batteries, please observe the following precautions:

• Unplug the power supply from the AC outlet.
• Disconnect the preamplifier from the power supply.
• Using a cloth or paper towel, rub a light coating of Vaseline or petroleum jelly on the inner walls of the battery pockets of the power supply chassis. This will prevent the batteries from becoming stuck in the future if there is any sort of swelling or shape increase. Note: Do not place the petroleum jelly directly on the battery, as it may cause you to lose control of the battery and drop it during installation."
philb7777
401 posts
 
Stew, the batteries aren't bad to replace. I sent mine in to JRDG, but thinking about it, they could probably just ship you the batteries and you could do it yourself.

I've used their email message service from their website and rarely get a response back, even after 2-3 weeks. When I call them they are usually very responsive. I just thought it was more 'polite' to email, but calling them gets you a response quicker.
magfan
1,583 posts
 
Do lead acid / Gel / glass matt batteries invert? I know my NiMh batteries can and do. The battery pack for my camera is 10 AA cells in series so if I have a weak cell, I'm a goner.
I'm working on a replacement / fix / rebuildable now since Canon gets 100$ and the aftermarket stuff sometimes is of suspect fit.
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