Wednesday 6 June 2018

Beware fake multi-meter leads

I bought these multi-meter leads on eBay for £2.99. They are advertised as "16PCS/Set Multimeter Probe Pin Test Leads Cable Multifunction Digital Clip Kit". I was attracted to them by the large number of accessories including pin type plugs that fit old analogue multi-meters.

When they arrived I discovered that the wires are steel and have a resistance of about 1 Ohm each, which makes them about as useful as a chocolate teapot. Any resistance measurement gets 2 Ohms added . Current measurements on the amps range drop large voltages, the wires get hot and would burn if left on for more that a few seconds.

Voltage measurements would be accurate enough but where the attachments screw on there is exposed metal, so not suitable for high voltages.

I got a full refund and get a set of these instead for £2.97.

They claim to be CE cat III rated for 1000V and 20A. Their resistance is only 64 milliohms. Not bad but my UNI-T UT61E came with 600V 10A rated ones that measure 44 milliohms and my EEVblog BM235 wins with 24 milliohms for 1000V 10A probes.

I got them to replace these old ones that belong to a multi-meter I inherited from my Dad. They have numerous burns from touching a soldering iron.

I dug out this old meter when I realised all my modern digital meters only go up to 1000V at most. This one goes up to 6KV!

I think it was purchased sometime in the early 1970s. It is branded Honor Model TE-12, made in Japan. I have seen identical ones on the web branded Lafayette. I don't think you would get away with connectors like that for 6KV nowadays!

1 comment:

  1. lol nophead why were you buying any type of test equipment part that cost £2.99, let alone leads? Would have figured you the type to buy the official Fluke lead kit what costs £50