rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 529 ONLINE 45 EVENTS SEARCH REGISTER  START HERE
 
1 page195 viewsPOST REPLY
A Main Hobbies . Boca Bearings . Modefo's RC Helicopters

.
.
Radio - Servo - Gyro - Gov - Batt > Min safe voltage is what? 4.5 volts?
 
 
rsilvers
Senior Heliman
Location: Marshfield, MA

I have a Gem 2000 and it was going off too soon, at 5.1 volts, so I am adjusting it. The manual says it should trip at 4.74 volts and you will have 30% power left. I think I want to run it close than that, especially since I tend to use an 1800 pack which will discharge at a slower rate than a typical pack.

I am running a GV-1, 6 LED lights, all digital servos, and a GY401, so I have fairly high power draw. What voltage would be safe to set it for? I am thinking 4.5 volts. Anyone have a suggested voltage?
04-07-2002 Over year old.
HOMEPAGE  
 
 
RC-CAM
Senior Heliman
Location: USA

The trouble with using the pack's voltage as a sign of an exhausted NiCd or NiMh is that the discharge curve is VERY shallow. If you choose a cutoff voltage that is too low, you are flirting with disaster.

I would not go lower than 1.18V per cell (with a C/5 load applied). In your case, adjust the GEM to warn you at 4.72V while drawing 350mA-400mA.

Then fly until the warning light comes on. Next, put the exhausted pack on your battery maintenance system and measure the remaining capacity. If it has about 30% remaining, your adjustments are correct.

Given the loads that your extra equipment is demanding, I highly suggest that you upgrade the Rx's on/off switch harness to a "heavy duty" type. The wimpy gauge wire that is on the standard harness will often cause false low battery voltage alarms under load.
04-08-2002 Over year old.
HOMEPAGE  
 
 
1 page195 viewsPOST REPLY
XHELI.COM . Autography FlightPower . Advantage Hobby

.
.
Radio - Servo - Gyro - Gov - Batt > Min safe voltage is what? 4.5 volts?
  UPDATE SCREEN   PRINT TOPIC Advertisers 

Subscribe to This Topic

Saturday, August 30 - 2:37 pm - Copyright © 2000 - 2008 runryder.com | email | link to rr | runryder needs cookie