Posts: 540
From: Aldershot, Hampshire, UK
Registered: Nov 2013
posted March 04, 2014 09:47 AM
Here's one on Ebay. You need to wire it up and put it in a suitable box which is not as easy as it sounds to make a good job of it.
Transformer 160VA 2X 15V Price for 1 Each - VTX-146-160-115
Posts: 540
From: Aldershot, Hampshire, UK
Registered: Nov 2013
posted March 04, 2014 10:00 AM
Sorry Mark, When I put the link in it wouldn't work and I tried again several times. Can't think what the problem is. If you go on Ebay put the title in the search box Transformer 160VA 2X 15V Price for 1 Each - VTX-146-160-115. Best Wishes.
What's important to know here is that when there are two secondary windings you really should connect them in parallel to operate at full power. The wire inside may or may not be capable of carrying the current at full power, and you wil not find out for sure until you melt something. Regardless, the thing will last longer if you use both anyway because it will run cooler.
(Also they have to be phased corectly when you connect them, or you will have a short circuit.)
-------------------- All I ask is a wide screen and a projector to light her by...
Posts: 1269
From: Thetford , Norfolk,England
Registered: May 2008
posted March 04, 2014 12:54 PM
In other words... for 150W 15 volt lamp supply...
"Live" is RED & YELLOW joined together "Neutral" is ORANGE & BLACK joined together
Mains input @ 230/250 volt to BLUE & BROWN
Excellent choice... toroidal wound giving very small external field and therefore less likely to cause "hum" in nearby audio circuits. Solid core, no mechanical noise. These Run cooler than conventional transformers. Very good price.
-------------------- Retired TV Service Engineer Ongoing interest in Telecine....
Posts: 1269
From: Thetford , Norfolk,England
Registered: May 2008
posted March 05, 2014 08:00 AM
Mark, A 150W lamp requires 10 amperes at 15 volts to operate properly... that's 15 (V) x 10 (A) = 150 (W). the suggested transformer in the links will supply 160 watts more than you require) if connected the way I specified.
The Maplin transformer is 15 volts at 1/4 Amperes (250mA). It can only run a 3.75 watt lamp.
The one in the links is what you need...period!
-------------------- Retired TV Service Engineer Ongoing interest in Telecine....
Posts: 1269
From: Thetford , Norfolk,England
Registered: May 2008
posted March 05, 2014 10:02 AM
It's only ONE transformer, which has TWO 15 volt windings, each capable of 80 watts. You have to connect the two 15 volt windings together to provide enough power to drive your 150 watt lamp, and you will have a margin of safety of 10 watts, which is OK and will not harm your lamp. You join the windings together exactly as I have explained earlier in the thread (use electrical connector blocks).
I explain it again here: There are 6 colour coded wires.... 1. Connect the mains Input to the BLUE and BROWN wires.If you use a switch, it goes in the BROWN wire which connects to the LIVE side of the mains.BLUE connects to the NEUTRAL side of the mains. 2 Connect RED & YELLOW together and connect them to one side of the lamp. 3. Connect ORANGE & BLACK together and connect them to the other side of the lamp
-------------------- Retired TV Service Engineer Ongoing interest in Telecine....