Portable calibrator repair attempt and success (Accidental connection to 220V)

[Kiriakos GR]

Even in the best houses shit happens, I was using this TE 1048 for several hours when I was testing software performance of TsDMMViewer.

At that day I was more tired than the calibrator and by the thought that my test cables were connected at the multimeter, I did connect the cables to Mains 220V.
But these test cables was actually connected to TE 1048 process calibrator. 
This thing has Max input protection up to 25V DC and internal circuity designed at handle a peak of no more than 50V DC.

Yes my loved TE 1048 were seriously injured and chances for repair / recovery these were looking very slim.
My first thought was that such over-voltage it did fried any Integrated Circuit in it  (IC) plus who knows what else.

By opening up my 1048 for inspection and damage assessment, I did notice a few PCB tracks them be totally burned.
Additionally few passive components were burned too beyond identification, and the PCB around those parts were also painted black from the blast.


Then I did contact my friends at Time Electronics in UK, and my email  were received by them, when 48 hours previously the entire UK got in lock-down due the Corona Virus.
Therefore my email (Help request about receiving an schematic) this find them at their homes.
 
Even so, I am very thankful  because they did find the way ( Thank you Brian !!) so I to receive help from one of their engineers who was having some files at his home computer.
And I did receive half schematic as assistance to parts recognition.

After making my own home work by inspecting this PCB (centimeter per centimeter) and its one component (all of them), I did succeed replacing anything burned by quality parts from my own stock.

And I did also restore point to point connection of any damaged PCB tracks and last stage this were careful entire PCB traces cleaning and removal of any blast marks residue.

Slowly and carefully and by every repair task this be made with precision and professionalism, in the fourth day the TE 1048 this shown first indication of LIFE 
At the fifth day (today), I did managed to restore entire of it functionality!!     

At the time of the accident the 1048 this were at DC Volt & Source mode, and therefore the internal volt meter this using ICL7129ACPL, this also received 220V at it measuring input and this is now half dead (half sorted).
By removing the (half sorted) ICL7129ACPL all support signals and reference voltages at the IC socket they were restored!!  (according to ICL7129ACPL schematic requirements).

Now I am in need for a new ICL7129ACPL which no one has in stock in Greece, but I did find a source in China (eBay).
This is an adventure that I will remember for my entire life time.   

Now I am in need for a spare part when entire planet this is at temporally lock down or almost. 

Either way the smile this returned back to my face and I am in celebrating mode !!  TE 1048 process calibrator this is alive and kicking, and factory calibration this is undamaged!
Now I am at hunting mode for the acquisition of a Not Fake MAXIM chip (to be continued.....) 


 

[Kiriakos GR]

This is a quick update. 

About 26 days ago I did order all necessary spare parts for my calibrator 100% as NEW restoration.
At Corona virus times, cargo transport this is moving but much slower than before. 

After a long waiting for a month time, my spare parts from China they did appear at Belgium, I am assuming now of another two weeks of added delay.   
I am also waiting for a precision resistor, I found stock in Italy and placed my order two weeks ago.
 

[Kiriakos GR]

We are getting back on the game!   

Our new stock arrived:
2x  ICL7129ACPL
10x IRF610
4x  12R 2W ±1% 50ppm/°C ROYALOHM MF02S 

Newer 12R will replace a 12R which was a poor choice at product assembly line, the old one was just half watt and it shown to overheat and getting discolored.

[Kiriakos GR]

Quick Update..

My Joy were taken away    by the discovery that both received IC they were half damaged and or the second were a FAKE printed one.

I were refunded but this incident added 50 days of delay in this project all ready.
Now I am getting ready to re-order from another seller.

[Marco1971]

ICL7129ACPL, a glorious descendant of the ICL7106.

Marco1917

[Kiriakos GR]

ICL7129ACPL, a glorious descendant of the ICL7106.

Marco1917

My first DMM at 1988 had one of these. 

This time I did order three ICL7129ACPL form China, after eight days the tracking indicating customs clearance in Greece, now I am assuming another one week of waiting. 

[Kiriakos GR]

After all those months I am still totally confused and totally disappointed regarding the purchase of the MAXIM Voltage-meter IC.

I thought that China this is the source of Evil, but now I were double-crossed by LittleDiode ltd in UK. 
While I did paid full price they shipped to me an ancient 26 years old IC that is half working.

After-sales service of  LittleDiode ltd  in UK this is terrible,  even within eBay the customer service of LittleDiode ltd this is again unacceptably poor.
I did request several times to receive actual product pictures before shipping and they are in denial.
After my report that I did receive an ancient half-working IC, they told me to send back the old so I to receive an replacement.

Shipping back to UK this is 4.5 Euros as return postage.
Therefore I did insist  having a picture of the IC that they plan to use as replacement.
AND I received DENIAL AGAIN in my request for a damn product picture.

After several emails, they came with the plan about them receiving the old, so them to offer to me a refund. 

I lost 35% of my money because of this piss poor company, I did wasted and lost significant time.
Now beginning of September , I am waiting for the response from Time Electronics UK about their help of delivering to me one working IC voltmeter.
 
 

 

[Kiriakos GR]

I do feel thankful to Times Electronics again !! 

I got stuck at troubleshooting the fried PCB, and my friends at TE U.K. they did decide to assist me, by the offering of one new blank PCB.
Yes I am determined to transfer one by one all electronic components from the old at the new PCB.

Greece now under a second lock-down, I will use the free time as opportunity so to bring the calibrator back to life.
Additionally, Times Electronics UK  service team, it did email me special technical documentation for Repair and Calibration.   

[Andrew-88]

May the force be with you !!      about the assembly. 
 

[Kiriakos GR]

Dear readers of ITTSB Blog this is the final report about this blog post.

Personally as expert in electronic repairs, I did my best in this project regarding troubleshooting and time spend, the help of TE about schematics and new delivery of PCB this was significant.

But my personal diagnosis this got deeper, and actual source of the problem ended to be software programing corruption at programmable IC and hart of 1048 Calibrator.
   
Volt meter IC  ICL7129ACPL this is also connected with PIC16C710 IC, when 1048 calibrator this accidentally connected to mains, portion of the electrical charge were transferred from ICL7129ACPL to PIC16C710.

Now my 1048 calibrator has recover functionality in most functions, but the damaged PIC16C710 IC this does not aloud  ICL7129ACPL to operate at High-resolution of digits.
But I got partially lucky, one FAKE  ICL7129ACPL  (with lower digits resolution) this is working on that circuit.

At that point, the team of Time Electronics UK, they were unable to remotely assist me any further.
Even so they decided to send to me another NEW 1048 calibrator 

I did a very good job repairing what was possible be repaired at my First 1048, and this is now fully capable to operate as Source when second 1048 this is connected as Measure unit.

 
I do recognize and appropriate all help received from Time Electronics UK.
They did proven, at least to me, that they are primarily humans with high values.

It is also unfortunate, that Brexit this is now effective and shipping for UK to EU along EU to UK, this is now considered as importation of goods.
This new change, now also forced  Time Electronics UK to make a new shipping note for customers out of UK.


THE END..