Hitachi Set Free

[Thermatech]

Most A/C manufacturers will suggest use analogue meter for testing 3ph inverter circuit components in the service manual so all quoted readings in the service manual are based on the use of analoge

You can use digital meter but you dont get acurate readings because its not ideal for measuring semi conductor components.
older type analogue meters are better suited for this type of measurments.

Different multi meters will all give slightly different readings depending on the meter specification & internal circuits configuration.
If using a multi meter you will often get better readings with diode mode instead of ohms mode.
But as the manufacturer quotes analogue ohms readings you cant get like for like using diode mode as the readings will be completely different.

For example in the Hitach service manual in inverter testing section it states 'do not use digital tester'

I spent some days in 2001 at the factory in Japan which makes Mitsubishi Electric City Multi VRF outdoor units. The R&D inverter engineer was absolutely adamant
that IPM & rectifier components should only be tested with analogue meter.

[al]

Coral/Thermatech

PM me and i'll send a copy of a bulletin received in June this year, happened to coincide nicely with our first major component failure in 5 years installing Hitahci!!

al