Platinum Printer Member
- Nov 27, 2010
- Reaction score
- Copenhagen Denmark
- Printer Model
- Canon MP990
I found a couple of tutorials here: http://www.youtube.com/watch?v=bF3OyQ3HwfU and here: http://learn.adafruit.com/multimeters/overview . If you are not too familiar with electricity/electronics be very careful. If you try to test voltage with the multimeter wrongly set to measure current you create a short circuit. Also mains voltage is dangerous, and some batteries like a large automotive 12V battery can create very high short circuit currents, several hundred amperes or maybe more than a thousand amperes! Even an AA NiCad or NiMH cell can create enough current to burn thin wiring. If you know somebody who is familiar with electronics, I suggest to ask him or her to demonstrate the use of the multimeter.ROX wrote:
...PeterBJ - I'm not really too familiar with a multimeter but I do have one. Can you tell me how to test with it? When I have time to tinker with it, i'll try it. I'd like to confirm what it is thats wrong...
I think you will have years of trouble free service from your Redsetter. The battery problems seem only to affect the very first models.barfl2 wrote:
Mine is the Redsetter bought I think from Octoinks had it about 18 months used regularly but do not do massive amount of resets. I took bottom off and it has a 3V Mitsibuishi battery CR3032 type. This should be a reliable manufacturer. I once was told by a local retailer that you should NOT check voltages of these button cells with a volt meter they had a seperate gadget they used
The reason for the advice that a voltmeter is not suited for testing batteries, is that the volt meter draws only a very small current, which could give a false good indication. The battery has an internal resistance causing the voltage to drop under load. When a battery is is getting used up, the no load voltage decreases and the internal resistance increases. The internal resistance may increase faster than the no load voltage drops. So the voltage should be measured when loading the battery with a suitable current. For testing the CR2032 I think a load resistor of 680 ohms will be suitable. This will draw approximately 5mA from a good CR2032, The 5 mA is approximately the current drawn by a newer model Redsetter when in use. I think that as long as the voltage of the battery is more than 2.8 V or 2.9V under load the battery is still good for use with the Redsetter. I think the special device is just a simple voltmeter in parallel with a suitable load resistor and housed in a small box.