Partridge Transformer ID - UK Vintage Radio Repair and Restoration Discussion Forum

Geoffbarber · 27th Jan 2020, 5:38 pm

Hi Folks,
Just came across this old Partridge Transformer in my spares box (see attached pictures) and I would appreciate if anyone had a current rating for the secondary, please?

I've connected a variac to the primary side (looks like 120v-0-120v) DC resistance across the 2 windings is 51 ohms. With 240 volts in I get 37.5v across the secondary (unloaded) which seems to match up with the 38V AC drawn on the transformer.

If anyone has anymore information relating to this transformer, It would be greatly appreciated.
Regards.
Geoff.

MotorBikeLes · 27th Jan 2020, 9:48 pm

The first photo shows 400v. maybe it is for producing (say) 50v from across two phases of a 3-phase supply for low voltage relays or whatever.
Les.

Herald1360 · 27th Jan 2020, 11:40 pm

That 400V is just the "mustard's" voltage rating.....

trobbins · 28th Jan 2020, 1:39 am

The H7765 is a datecode style marking, it progresses in time with Partridge parts, and from my tracking it would indicate post 1974, but that is a bit hazy due to limited samples I have come across with dates.

I don't have any part catalogs after 1965, but commercial batches started to use TDxxxx from early 1960's for PT's, OT's and chokes (I have a TD2183 power Tx) and HiWatt initially had TDxxxx part numbers, then TG, then THxxxx, then TKxxxx, from what I can perceive.

It could be a power transformer, if you were able to confirm primary current level and current waveform with 240Vac. The other option is an output transformer.

Ed_Dinning · 28th Jan 2020, 7:42 am

Hi Geoff, if you can mike the leadout wires and find their diameter then you can work backwards on the basis of a normal rating of 3A/mm^2

Ed

Silicon · 28th Jan 2020, 11:45 pm

The winding ratio is either 6.4 : 1 or 3.2 : 1.

Could it be an interstage transformer?

27th Jan 2020, 5:38 pm	#1
Geoffbarber Triode Join Date: Apr 2013 Location: Scarborough, North Yorkshire, UK. Posts: 22	Partridge Transformer ID Hi Folks, Just came across this old Partridge Transformer in my spares box (see attached pictures) and I would appreciate if anyone had a current rating for the secondary, please? I've connected a variac to the primary side (looks like 120v-0-120v) DC resistance across the 2 windings is 51 ohms. With 240 volts in I get 37.5v across the secondary (unloaded) which seems to match up with the 38V AC drawn on the transformer. If anyone has anymore information relating to this transformer, It would be greatly appreciated. Regards. Geoff. Attached Thumbnails

27th Jan 2020, 9:48 pm	#2
MotorBikeLes Nonode Join Date: Dec 2012 Location: Kirk Michael, Isle of Man Posts: 2,350	Re: Partridge Transformer ID The first photo shows 400v. maybe it is for producing (say) 50v from across two phases of a 3-phase supply for low voltage relays or whatever. Les.

27th Jan 2020, 11:40 pm	#3
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Partridge Transformer ID That 400V is just the "mustard's" voltage rating..... __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

28th Jan 2020, 1:39 am	#4
trobbins Heptode Join Date: Oct 2009 Location: Melbourne Australia Posts: 901	Re: Partridge Transformer ID The H7765 is a datecode style marking, it progresses in time with Partridge parts, and from my tracking it would indicate post 1974, but that is a bit hazy due to limited samples I have come across with dates. I don't have any part catalogs after 1965, but commercial batches started to use TDxxxx from early 1960's for PT's, OT's and chokes (I have a TD2183 power Tx) and HiWatt initially had TDxxxx part numbers, then TG, then THxxxx, then TKxxxx, from what I can perceive. It could be a power transformer, if you were able to confirm primary current level and current waveform with 240Vac. The other option is an output transformer.

28th Jan 2020, 7:42 am	#5
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: Partridge Transformer ID Hi Geoff, if you can mike the leadout wires and find their diameter then you can work backwards on the basis of a normal rating of 3A/mm^2 Ed

28th Jan 2020, 11:45 pm	#6
Silicon Nonode Join Date: Jun 2007 Location: Coulsdon, London, UK. Posts: 2,163	Re: Partridge Transformer ID The winding ratio is either 6.4 : 1 or 3.2 : 1. Could it be an interstage transformer?