The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#115691 - 12/04/03 01:28 PM Water Heater (German)
Webmaster Offline

Administrator
Member

Registered: 10/07/00
Posts: 3142
Loc: NY, USA
 Quote:
As the pump of our 4.5kW water heater started to make unusual noises, i removed the covers and the steerings cover, to find the heating element was connected to the contactor with totally rusty ferrules, one was just soldered and screwed in. so i removed the corrosed parts, cut a bit of the cable as there was enough spare, removed the insulation, to find all the copper strands were black. not overheated, corrosed. I decided to change the whole cable, traced it to a cover on the heating element, removed the cover to see this:
 Quote:
thanks pump for failing otherwise i'd never found this time bomb. imagine there were 4500W running on almost daily...

greetings
:andy:

Top
Tools for Electricians:
#115692 - 12/05/03 03:33 AM Re: Water Heater (German)
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Not good. Is this a 3-ph 400V heater?

Top
#115693 - 12/05/03 05:01 AM Re: Water Heater (German)
C-H Offline

Member

Registered: 09/17/02
Posts: 1508
Loc: Stockholm, Sweden
I'm not sure what it was originally, but it sure isn't whatever it was anymore!

Top
#115694 - 12/05/03 06:37 AM Re: Water Heater (German)
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
 Quote:
I'm not sure what it was originally, but it sure isn't whatever it was anymore!
Yes .... But can you say that 3 times fast?


Bill

Top
#115695 - 12/05/03 06:58 AM Re: Water Heater (German)
:andy: Offline
Member

Registered: 10/18/03
Posts: 272
Loc: Germany
this is a three phase 400V-delta heater.
i dont want to know if the heating element or the terminals were hotter when running...

i forgot to mention the age: 25 years. i'd thaught the corrosion protection would be a *bit* better, humm....

the wire under the green-yellow one is blue at the other end of the cable

i couldnt find out if the connections ever were made fine (ferrules or soldered wire), as i couldn't get the terminals open yet... the water is warmed up by our central oil heating in the winter, the electric heating is just needed in summer, but i think i'll just leave it that way and shut the electric part down.

you can view a picture in 1280x960 at http://320036920636.bei.t-online.de/ECN/RIMG0109.JPG (~200kB)


[This message has been edited by :andy: (edited 12-05-2003).]

Top
#115696 - 12/05/03 07:52 AM Re: Water Heater (German)
C-H Offline

Member

Registered: 09/17/02
Posts: 1508
Loc: Stockholm, Sweden
Bill, I tried and the third time I read it "I'm sure not what I was..."

Andy, I didn't think connections could go that bad. Wonder how many volts were left for the heater once the connections had taken their share...

BTW. Is this a hot water cylinder? 4.5kW seems to little for a instantaneous water heater.

[This message has been edited by C-H (edited 12-05-2003).]

Top
#115697 - 12/05/03 09:09 AM Re: Water Heater (German)
:andy: Offline
Member

Registered: 10/18/03
Posts: 272
Loc: Germany
its a cylinder, about 150-200 liters i guess


i still couldnt figure about the connection. what do you think is under the screw? soldered, ferrule or bare wires?




[This message has been edited by :andy: (edited 12-08-2003).]

Top
#115698 - 12/06/03 02:56 PM Re: Water Heater (German)
mvpmaintman Offline
Member

Registered: 09/15/03
Posts: 113
Loc: Manhattan, Kansas, USA
Maybe a split bolt of some kind??
Orjust darn good luck for Any

Top
#115699 - 12/06/03 09:12 PM Re: Water Heater (German)
SvenNYC Offline
Member

Registered: 08/19/02
Posts: 1685
Loc: New York City
I see what looks to be the slot in the head of a screw.

Look at the vertical channel of sorts running north-east/southwest.

It's definitely a screw - probably with a little pressure plate to clamp against the wire. You don't want to tin wires that go under a screw. The solder will "creep" and the connection will eventually work itself loose from heat cycling.

Top
#115700 - 12/07/03 04:42 AM Re: Water Heater (German)
:andy: Offline
Member

Registered: 10/18/03
Posts: 272
Loc: Germany
i knew its a screw, i just ask myself how the wire was made up before screwed in.

Top
Page 1 of 2 1 2 >



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals