battery adjustment on DSC MaxSYS
Dan Lanciani
What is the function of the trim pot on the DSC 4020 panel and 4204 relay
module? I thought at some point that I saw it mentioned in one of the manuals
as having something to do with the battery charge bias, but now I can't find
it anywhere. I'm interested because of the following (possibly unrelated)
problem:
After < 1/2 hour with AC off, the main panel complains of a low battery
condition. The battery is a relatively new 7Ah unit. When the low-battery
warning starts, the terminal voltage is still > 12V. With AC on, the
float voltage measures > 14V. The manual suggests that the voltage should
be below 12V before the warning.
I have a larger wet cell on the 4204 (I realize that this makes the comparison
less than useful) and its charge float voltage is 13.6V. The 4204 has never
reported a battery problem during a power failure, but again that doesn't
prove much...
If the pot controls float voltage and/or warning threshold, the one on
the main panel might be set a bit off.
Dan Lanciani
ddl@danlan.*com
eric
Dan Lanciani wrote:
> What is the function of the trim pot on the DSC 4020 panel and 4204 relay
> module? I thought at some point that I saw it mentioned in one of the manuals
> as having something to do with the battery charge bias, but now I can't find
> it anywhere. I'm interested because of the following (possibly unrelated)
> problem:
With a 1k resistor across the battery leads, adjust the pot for 13.8 VDC charging
voltage across the resistor (remove the battery of course).
> After < 1/2 hour with AC off, the main panel complains of a low battery
> condition. The battery is a relatively new 7Ah unit. When the low-battery
> warning starts, the terminal voltage is still > 12V. With AC on, the
> float voltage measures > 14V. The manual suggests that the voltage should
> be below 12V before the warning.
Battery has probably cacked it, sometimes you get defective batteries.
Maybe you can't power six keypads, eight PIR's, five smokes and three gas
detectors from one 7Ah battery? (that was a problem I had last year, came up as
low combus power, check in the 4204 manual about repowering the combus, it uses
the first relay output).
eric.
Jim Rojas
Hi Eric. I would not suggest powering all those devices on the panel directly. I
would use a secondary power supply for all the devices. If you are using two wire
smokes, leave them connected to the panel for power.(obivously) You can easily
install a relay to monitor the external power supply. I believe DSC makes a power
supply that can boost power & also be supervised. I've installed quite a few 832's,
Power is usally a problem. If you need to switch off the power via PGM for resetting,
use a small relay. I always use a power supply & a small relay every time a customer
wants more than 2 sirens.
Jim
Dan Lanciani
In article <34EC77A8...@technologist.com>, e...@technologist.com (eric) writes:
[...]
|With a 1k resistor across the battery leads, adjust the pot for 13.8 VDC charging
|voltage across the resistor (remove the battery of course).
So it sounds like the pot adjusts the charge float voltage only and doesn't
affect the warning threshold voltage, right?
|> After < 1/2 hour with AC off, the main panel complains of a low battery
|> condition. The battery is a relatively new 7Ah unit. When the low-battery
|> warning starts, the terminal voltage is still > 12V. With AC on, the
|> float voltage measures > 14V. The manual suggests that the voltage should
|> be below 12V before the warning.
|
|Battery has probably cacked it, sometimes you get defective batteries.
That was my first thought, so I measured the terminal voltage at the time
the warning starts (it is really only about 10 minutes after removing
power). At that point, the battery terminal voltage is still > 12V.
According to the 4020's manual, the warning is not initiated until the
voltage is <= 11.3V. This suggests to me that something is wrong with
the panel's threshold detector. Unless the battery is fooling my meter. :)
|Maybe you can't power six keypads, eight PIR's, five smokes and three gas
|detectors from one 7Ah battery?
Maybe so, but I'm running only two keypads and one smoke off the main
panel's supply. (Everything else is on the 4204.) If 7Ah isn't enough
for this then I'd hate to think what the manufacturer's recommend 4Ah
minimum would do...
|(that was a problem I had last year, came up as
|low combus power, check in the 4204 manual about repowering the combus, it uses
|the first relay output).
My 4204 is quite happy with its big (marine, deep cycle) wet cell. I
may put one of those on the main panel as well, but I liked the idea of
having everything necessary to keep the siren running (after an alarm)
contained within the main box: no accessible wires can be cut to silence
the noise.
Dan Lanciani
ddl@danaln.*com
Robert L Bass
Jim Rojas wrote:
>
> I would not suggest powering all those devices on the panel directly.
Please note that Dan's Maxsys system includes the DSC PC4204 Auxiliary
power supply module. He has a separate 12V/7AH battery and transformer
for the module. The 4204 specs are as follows (from my Web site):
Provide 1.5 Amps @ 12.5 VDC to Power Additional Modules,
Devices and Siren Outputs
Includes 4 Fully Programmable High Current Form 'C' Relays
- Rated at 10 Amps @ 125 VAC
Each Relay Programmable to Activate for any of 28 Options
The power output of the 4204 should be sufficient to handle all of the
modules and auxiliary devices in Dan's system. I'll check with tech
support about the Low Batt report. If it's a bad battery, Dan, just
contact me via e-mail and I'll get you a replacement.
Blue Skies,
Robert L Bass
========================>
Bass Home Electronics >
80 Bentwood Road >
W Hartford, CT 06107 >
alar...@BassHome.com >
http://www.BassHome.com >
860-561-9542 Voice >
860-521-2143 Fax >
========================>
Robert L Bass
Dan,
What deep cycle battery are you using (make/model)? Also, if the 4020
is signaling low batt at >12V, that's covered under warranty. Contact
me and I'll get it fixed for you.
Regards,
Robert L Bass
--