ITTSB.EU Blog Forum

ITTSB Blog Specific => ITTSB - Small projects by Kiriakos & User reviews => Topic started by: Kiriakos GR on October 22, 2014, 07:35:18 PM

Title: Gossen Metrawatt Metrahit 15S DMM tear down
Post by: Kiriakos GR on October 22, 2014, 07:35:18 PM

This meter arrived to me for an inspection from another friend from Greece.
Even as out of warranty, Gossen was kind to offer to me technical documentation and few suggestions. 
I like to thanks Mr. Hans Decker  GMC-I Service GmbH

In public view the inner parts of Metrahit 15S  :)
 

Title: Re: Gossen Metrawatt Metrahit 15S DMM tear down
Post by: giavra on October 22, 2014, 08:23:00 PM

Marvellous post very useful  ;) 

Title: Re: Gossen Metrawatt Metrahit 15S DMM tear down
Post by: giorgos on October 23, 2014, 07:11:39 PM

This meter had to be repair? or you just opened it ?
Any impressions from this, did you make measurements?

Title: Re: Gossen Metrawatt Metrahit 15S DMM tear down
Post by: Kiriakos GR on October 23, 2014, 07:30:43 PM

This meter came in due a complain for unstable operation at mA range.
To disassemble and assembly back the range switch is a pain in the ass.
Now I am at the last stage to solder back the banana inputs, and the next step is long running tests.
At that point I am just 100% sure that range switch and PCB contamination is out of the game.   

Title: Re: Gossen Metrawatt Metrahit 15S DMM tear down
Post by: Kiriakos GR on October 23, 2014, 08:45:36 PM

My quick tests shown that this meter other than stable operation is close enough to be described as spot on.
Tomorrow I will do an 100mA long running test as soon I discover how to disable the auto-power off timer.

(yes I have screen protectors in all my meters, do not do a beauty contest)  :)

Title: Re: Gossen Metrawatt Metrahit 15S DMM tear down
Post by: Kiriakos GR on October 23, 2014, 08:53:57 PM

Quote from: giorgos on October 23, 2014, 07:11:39 PM

Any impressions from this, did you make measurements?

It is a 3000 counts with a sweet looking display.
It seems to have 4-5 measurements per second display update rate at DC, but at ACV is slow as 2-3 times max.