However, I don't think it will work for rpm. For this run a simple search and replace (\d)rpm with $1 rpm using regex. Same applies to Volts. You can adapt this to make the search and replace working for several units: (\d) ?(rpm|V|mV)\b and $1 §2
Any further units must be added separated by the pipe | each.

Jerzy, thank you. As mentioned in the previous post "When there are mm or cm measurements in the source, the non-breaking space gets added thanks to the setting under auto substitution. " I was referring to literally this setting that I'm already using. As you are saying, it is not working for rpm, volts or similar.

Would it be possible to use these regex statements for auto substitution in some way instead of find / replace? I have just started on a fresh project and am asking so that I can solve this issue before I start working on the translation.

You could try to use Regex Match Auto Suggest Provider: Regex Match AutoSuggest Provider - Language Solutions | SDL

Thank you Jerzy, I have now downloaded the add-in. I'm trying to set up my regex substitution ((\d+)(rpm|RPM|V) as regex pattern), but I am having problems with the replace pattern.

At the moment I got this: $1\xa0$2

I am trying to set up a non-breaking space between $1 and $2. It works in a regex tester online, but not in Trados. It literally replaces with "\xa0". 

Do you know how I can implement a non-breaking space here? It should be decimal 160 or hex U+00A0.

Thank you!

Thank you Jerzy, I have now downloaded the add-in. I'm trying to set up my regex substitution ((\d+)(rpm|RPM|V) as regex pattern), but I am having problems with the replace pattern.

At the moment I got this: $1\xa0$2

I am trying to set up a non-breaking space between $1 and $2. It works in a regex tester online, but not in Trados. It literally replaces with "\xa0". 

Do you know how I can implement a non-breaking space here? It should be decimal 160 or hex U+00A0.

Thank you!

The easiest way to enter a non-breaking space in the replacement option is to copy it literally from a segment in Studio. Otherwise you can also press and keep ALT and enter 0160 with your num-pad, which will insert a NBSP everywhere in Windows.