UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Components and Circuits

Notices

Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets.

Closed Thread
 
Thread Tools
Old 6th Aug 2019, 8:14 pm   #1
Ed_Dinning
Dekatron
 
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,173
Default NTC

Hi Folks, has anyone information on a Siemens Matsushita inrush limiter type S10 (or 510)
K300.
It was used for inrush limiting on a battery charger for a floor sweeper (conventional transformer type)

Thanks, Ed
Ed_Dinning is offline  
Old 6th Aug 2019, 8:35 pm   #2
McMurdo
Dekatron
 
McMurdo's Avatar
 
Join Date: Jun 2009
Location: Staffordshire Moorlands, UK.
Posts: 5,263
Default Re: NTC

hi ed, I think that's a varistor

300V AC RMS, 385V DC
__________________
Kevin

Last edited by McMurdo; 6th Aug 2019 at 8:36 pm. Reason: added brief spec
McMurdo is offline  
Old 6th Aug 2019, 9:30 pm   #3
Ed_Dinning
Dekatron
 
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,173
Default Re: NTC

Hi Kevin, I thought that at first, but it in series with the incoming supply and when linked out it allows things to power up.
The surprising thing is that it does not look as if it has seen any heat and measures o/c on a DVM.

Ed
Ed_Dinning is offline  
Old 6th Aug 2019, 9:39 pm   #4
McMurdo
Dekatron
 
McMurdo's Avatar
 
Join Date: Jun 2009
Location: Staffordshire Moorlands, UK.
Posts: 5,263
Default Re: NTC

If it looks like the one below, it's definitely a varistor, the S10 means 10mm disc and the K300 means rated for up to 300V AC.

Epcos (siemens/TDK) varistors are invariably blue with the short part number marked in white, and the NTC thermistors are invariably black (or formerly grey in the Siemens & Halske days) and are usually marked NTC..and the cold resistance value.
Attached Thumbnails
Click image for larger version

Name:	mov.jpeg
Views:	67
Size:	54.3 KB
ID:	187952   Click image for larger version

Name:	ntc.jpeg
Views:	56
Size:	20.4 KB
ID:	187953  
__________________
Kevin
McMurdo is offline  
Old 6th Aug 2019, 11:28 pm   #5
turretslug
Dekatron
 
turretslug's Avatar
 
Join Date: Nov 2011
Location: Surrey, UK.
Posts: 4,385
Default Re: NTC

Do you know of any "recent history" of this charger Ed- is it possible that someone else has previously had a go, say mis-wiring the mains input side when replacing a damaged supply cable and putting it aside when it failed to work? I agree with Kevin that it sounds very much like a Siemens MOV code as applied to these shiny blue disc devices, rather than the matt black finish NTCs,

Colin
turretslug is offline  
Old 6th Aug 2019, 11:30 pm   #6
joebog1
Banned
 
Join Date: Jun 2015
Location: Mareeba, North Queensland, Australia
Posts: 2,704
Default Re: NTC

https://www.conrad.com/p/disk-varist...0-1-pcs-531204

I think thats the one Ed

Joe
joebog1 is offline  
Old 7th Aug 2019, 9:06 am   #7
Ed_Dinning
Dekatron
 
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,173
Default Re: NTC

Hi Gents, thanks for the info, I agree it looks very like a varistor.

The charger is for a floor scrubber and appears to have been faulty for months.
There does not appear to have been any changes/ replacements on the PCB at all, but I'll try and draw the circuit to see what goes where. From memory it was in circuit with a mains switching relay which then fed the (conventional) transformer.

The joys of faultfinding when there is no documentation, no money and people are now used to throwing away the information!

Ed
Ed_Dinning is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 11:48 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.