JRDG Coherence II; Battery Display Issue

Phil:
Would you happen to know if it is ever normal for both FULL and LOW lamps to be dark? Is the performance of the unit compromised in this state? How would one normally determine when it is time to replace the battery? What did you notice?Thanks for the response.

I noticed exactly what you described and then when testing battery life it was significantly shorter. On my BPS1 I can get around 6-8 hours a continuous battery play. When the batteries were near the end of thir life, I could only get an hour or less.

Guido is right though - might be worth trying to cycle them.

Stew, as mentioned in my PM, there is an entry in the JRDG knowledge base that suggests that one of your batteries may have failed and may need replacement. See:

http://jeffrowlandgroup.com/kb/questions.php?questionid=464

The Coherence II manual at

http://jeffrowlandgroup.com/kb/questions.php?questionid=488

discusses battery operations in the following paragraphs:

A MODE SELECT push button: Momentarily pressing this button switches
the power supply between AC and BATT operational modes. Either the
BATT lamp or the AC lamp will be illuminated. Note: BATT mode is not
allowed unless the batteries have achieved sufficient charge capacity.

...

Upon initially connecting AC power, it may be necessary to press and hold
down the MODE button (2) for five (5) seconds to initially boot-up or
reset the charge management system located within the Power Supply. In
a few seconds, the AC mode lamp will light and the Preamplifier INPUT 1
And RECORD 1 lamps will illuminate.
The Coherence Preamplifier is designed to be powered from the AC mains
which automatically initiates battery charging as necessary and is indicated
by the illumination of the AC mode lamp. However, the Preamplifier is still
powered by the internal batteries. AC mains power is disconnected from
the power supply internally whenever the BATT mode is selected using
the MODE push button. Under this operating condition, the preamplifier
operates exclusively from the internal batteries. Up to fifteen (15) hours of
operation in this mode is possible depending upon the initial state of
charge of the internal batteries.
If the Preamplifier is not used for an extended period of time and/or a
source of AC power will not be available, AC power should be removed
and the MODE push button should be pressed and held down for
approximately five seconds. A slight click will be heard. No lamps should
be illuminated. This feature allows the preamplifier to be stored or
shipped without discharging the internal batteries.

If the FULL charge lamp is illuminated, the battery capacity will range
between 50-100% of full charge. This lamp will not illuminate shortly after
the BATT mode is selected.
If the LOW charge lamp is illuminated, the battery is significantly
discharged and will automatically switch back to AC mode to commence
charging. If AC mains power is not available under these conditions, then
the Power Supply will automatically switch off, thus preventing the
batteries from becoming overly discharged.
The Power Supply is intended to operate connected to active AC mains at
all times. The charge management system only permits operation at the
voltage indicated on the rear panel. If an incorrect AC line voltage is used,
all of the Power Supply front panel lamps will flash on and off simultaneously
approximately four times per second.

...

Battery Complement 2 each 12 volt, 7.2 amp/hour
user replaceable sealed, lead calcium,
maintenance-free batteries
Battery Service Life 5-8 years
AC Unassisted Run Time 14-18 hours based upon
initial battery full charge

G.

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

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.