Protek - Their production line is just too fast

[Psi]

I was just using one of my DMMs and remembered something about it that i'd forgotten for many years.

Check out the Protek 506 DMM




Looks pretty standard for a mid range multimeter.


Now see what it looks like when you take off the rubber cover.



This DMM hasn't been put in an oven or exposed to extreme heat.

I got the unit from jaycar many years ago and it's been like that from new.
I didn't return it to jaycar because i misplaced the reciept, and also it's an odd kind of issue to try and get a replacement on, it looks so much like user abuse.

It seems the protek DMM production line was cranking these units out so fast that they could get the rubber cover on them before the plastic case had cooled down from the injection molding 

[mobbarley]

wow! my 506 is not like that! It does look like that now from the hard life it has lived after providing many years of service. lots of features in it too, i upgraded to a fluke 287 and still keep the protek around.

[sonicj]

I was just using one of my DMMs and remembered something about it that i'd forgotten for many years.

sounds like now might be a good time for battery swap! 
-sj

[mikeselectricstuff]

Looks more like damage from plasticiser leeching from the cover

[Psi]

I was just using one of my DMMs and remembered something about it that i'd forgotten for many years.

sounds like now might be a good time for battery swap! 
-sj

yeah, i hardly ever use it, it's probably all leaked inside. Better have a look.

[Psi]

Looks more like damage from plasticiser leeching from the cover

interesting, whats that?

[Fraser]

I've not seen this before with a multimeter holster but regularly see 'plugpack' or 'brick' power supplies with deep furrows melted into their cases. The furrows are caused when people wrap the power cable around the unit for storage. The insulation of the cable reacts with the ABS plastic of power supply case and melts itself into the surface. It's an odd phenomenon and seems worse when units have been stored in warm environments like lofts. Not all plastic/cable combinations suffer this effect. A more severe reaction often occurs between cable insulation and polystyrene packing material. I have found cables covered in melted polystyrene after having been in direct contact with the packing for long periods of time.

As has been suggested, this is some sort of chemical reaction between dissimilar materials and their respective chemical components and excretions. It can really ruin your day to find that your carefully stored piece of plastic cased equipment has been 'etched' by contact with it's own mains cable..... been there, seen that     Many years ago I was told that a new cars plastic parts excrete solvent vapours for some months after manufacture. I presume these are part of the 'new car' smell that some are lucky enough to experience 

In your case, there appears to have been a really severe reaction in the period between manufacture and your purchase. A possible manufacturing error in the holster material mix maybe ? Thanks for sharing this though..... it highlights the issue of damage due to disimilar plastics etc.

[Psi]

i guess it's possible that my rubber case was dropped on the floor or was dirty during assembly and someone gave it a clean with some sort of solvent but didnt clean off the excess before putting it on the meter.

[mikeselectricstuff]

Looks more like damage from plasticiser leeching from the cover

interesting, whats that?

Plasticiser is used in soft plastics e.g. PVC wire, soft insulating covers etc. Sometimes this can leech out and soften hard plastics in contact with them over time (typically months to years), and this typically looks like melting. Here's an example where a croc-clip cover was in contact with an ABS case.

[Edison]

Deformation of drawer after contact with crocodiles - blast plasticizer

[mikeselectricstuff]

Is this a new Necroposting record ?

[mairo]

My Protek 506 (my first DMM, apat from the $5 that I got at uni) also has this issue. It has not been exposed to any excessive light/heat and I also think is something to do with the chemistry b/w the rober cover and the DMM plastic.

[helius]

My Protek 506 (also my first DMM) was bought used without a boot, and is unaffected by this problem (although the cover of the RS232 port was lost long ago). It still works OK but needs to be calibrated.

[thm_w]

My Protek 506 (also my first DMM) was bought used without a boot, and is unaffected by this problem (although the cover of the RS232 port was lost long ago). It still works OK but needs to be calibrated.

If you have a good reference you can cal it yourself:
- Take off back cover
- Switch cal switch in top right to ON position
- Power on meter (to volts)
- Apply the required voltage/current if you have it and press "OK"
- If you don't have it press right arrow to skip that step

If it asks for A or mA of course you have to switch to the correct range. I couldn't find a way to go back, only forward.

[picrthis]

I know this this thread is old, but does anybody have the original disk with the software & drivers on it they could zip-up and send me?
Please

[coromonadalix]

image of a floppy ??

https://archive.org/details/protek-506-rs232c-driver-diskette

and this thread

https://www.eevblog.com/forum/news/protek-506-review/

was known as a voltcraft 506


and maybe this piece of software ??
http://www.multimes.de/download.htm

[picrthis]

Thanks I had found that earlier but I noticed some of the files included are a bunch of file fragments and was hoping for a cleaner copy, I do appreciate it though.

[Psi]

I found an old zip file i had, might be what was on the disk.
Looks about right, has the dos and windows app.