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 Mulitimeter
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 Return to top of page · Post #: 1 · Written at 8:32:21 AM on 2 March 2017.
Nesser's Gravatar
 Location: Seneca Falls, US
 Member since 2 March 2017
 Member #: 2073
 Postcount: 1

I have a Micronats 22-220 mulitimeter that works only on Ohms no AC or DC. any help would be welcome.


 
 Return to top of page · Post #: 2 · Written at 1:40:14 PM on 2 March 2017.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 923

Hi Nesser, if the ohms works that means that the probe leads and most of the meter are intact and working. I am assuming that when you say the ohms is working it actually reads CORRECT value that is a 100 ohm resistor reads 100 etc.
If the volts AC and DC don't work and its not because a probe lead is plugged into the wrong socket or open circuit,

1/ CHECK the input fuses if fitted.
2/ LOOK for any signs of blown wires/PC tracks or burnt parts. That usually happens when the meter is set/plugged into ohms or milliamps and then connected straight across the 110/240 mains. The meter then goes booooom inside and functions don't work. Sometimes a fuse if fitted will blow or a pc track pop and fixing that will restore function.
3/ If nothing found or if its blown up throw it in the bin and replace.
Yes I used to fix things like multimeters until I worked out that fixing $30 meters at an overhead of $60 an hour lost me money!
Cheers, Fred.


 
 Return to top of page · Post #: 3 · Written at 1:44:37 PM on 2 March 2017.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6172

 
 Return to top of page · Post #: 4 · Written at 8:30:30 PM on 2 March 2017.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4506

The one I have is marked as being bought 1993 and is a 22-220A Fuse is 0.5A 250V. How long is it since it has been used? Did it just happen suddenly? My book does not have a circuit.

Beware of modern batteries. There are two brands, one made in China the other Indonesia, that are on my black list for leaking well before the expiry date on the side and before they a flat.

Marc


 
 Return to top of page · Post #: 5 · Written at 8:48:21 PM on 2 March 2017.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6172

My book does not have a circuit.

Schematic can be downloaded from the link I gave above.


 
 Return to top of page · Post #: 6 · Written at 10:09:31 PM on 2 March 2017.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 4506

Realised it could be downloaded, but it is common with many to have the circuit in the book, even that it is likely not fixable. At this point with the one in question the history of it & the mechanics are more relevant than the circuit. It first needs to be examined for any signs of corrosion, tampering, or breakages and a blown fuse.

The battery holding part of my 22-167 and others I have repaired, have over time, been damaged by scanting and sudden deceleration when impacting concrete and the batteries themselves.

Operators can produce some interesting effects destroying them. Measuring the OP of a Microwave transformer & the resistance of a 415V rail being two I have seen described in the accident report.


 
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