Reconn's World Forum - Battery Power Monitors various circuits used to monitor the strength of a battery http://www.reconnsworld.com/forum/list.php?14 Wed, 08 Sep 2010 23:44:04 -0700 Phorum 5.2.9a http://www.reconnsworld.com/forum/read.php?14,316,316#msg-316 Servo power monitor (no replies) http://www.reconnsworld.com/forum/read.php?14,316,316#msg-316
Need to monitor the power to a r/c servo and turn on a led when the power is being excessively drained such as would occur if a control surface was binding the free movement of the servo or causing the servo to draw to much power from wear to the mechanical parts of the servo reducing free movement.]]> gellwood Battery Power Monitors Fri, 01 Jul 2005 12:33:40 -0700 http://www.reconnsworld.com/forum/read.php?14,6,6#msg-6 LM3914 battery monitor (3 replies) http://www.reconnsworld.com/forum/read.php?14,6,6#msg-6

parts:
U1 LM3914 Bar-Dot Generator IC
R1 100k ohm potentiometer
R2 1k ohm resistor
LED1-10 light emitting diodes

all resistors are 5 or 10 percent tolerance, 1/4-watt
this circuit should be powered by its own battery, otherwise you might get an innacurate reading. hook the to-be-monitored battery to pin 5 of the chip.]]> andrew Battery Power Monitors Mon, 22 May 2006 07:32:15 -0700 http://www.reconnsworld.com/forum/read.php?14,5,5#msg-5 12 volt battery monitor (5 replies) http://www.reconnsworld.com/forum/read.php?14,5,5#msg-5

parts:
R1 10k ohm potentiometer
R2, R3 1k ohm resistor
D1 6 volt zener, 1 watt
Q1 2N3904 npn transistor
LED1 light emitting diode

all resistors are 5 or 10 percent tolerance, 1/4-watt
R1 controls the trip-point of the circuit. when the voltage falls below the trip-point, the led lights. adjust it to the desired level. to use this circuit to monitor a 6v battery, substitute D1 for a 3.3 volt zener diode and adjust R1 accordingly.]]> andrew Battery Power Monitors Tue, 13 Oct 2009 10:15:40 -0700 http://www.reconnsworld.com/forum/read.php?14,4,4#msg-4 "high" or "low" voltage battery monitor (6 replies) http://www.reconnsworld.com/forum/read.php?14,4,4#msg-4

parts:
U1 LM741 op amp IC
R1 100k ohm potentiometer
R2, R3 10k ohm resistor
R4 330 ohm resistor
LED1 light emitting diode

all resistors are 5 or 10 percent tolerance, 1/4-watt
R1 controls the trip-point of the circuit. adjust it accordingly. to reverse the logic (have the led light up when the battery has at least X amount of power,) connect the led to ground through R4.]]> andrew Battery Power Monitors Thu, 29 Jul 2004 05:53:10 -0700