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Products => Test Equipment => Topic started by: IanB on January 09, 2013, 06:00:45 am

Title: TTi EL302P Power Supply
Post by: IanB on January 09, 2013, 06:00:45 am
I've just been having a quick play with my new EL302P power supply from Thurlby Thandar Instruments. This thing is beautiful. It is, as Dave would say, "sex on a stick".

Some reasons I like it include a digital display with rotary encoder control knobs for voltage and current, a small case (about the size of the Rigol DS1102), dead quiet fan-less design, and very robust regulation. Using the control knobs you can dial voltages to exact decimals like 8.32 V and the output voltage matches on my multimeter to the display resolution. I dial in 8.00 V and my DMM says 8.00 V. When the output is off you can dial the current limit directly without having to short the output terminals.

The output side has been tuned with the current loop much faster than the voltage loop, so that the current limit is rigorously obeyed. That suggests to me that it would be very hard to blow things up accidentally by momentary over current. The voltage regulation is slow and smooth with no detectable overshoot in any of the tests I have performed. If I connect a 12 V automotive bulb the current limit reacts fast enough to catch and stop the cold filament current surge.

When switching on the output the voltage ramps to the limit and sticks there. Load regulation is fast, but not at the cost of the device being powered. For instance when I added a significant load instantaneously the voltage blipped about 80 mV away from the 10 V set point before recovering.

For one illustration of the output voltage response, the trace below shows the result of setting the voltage limit to 10 V, the current limit to 30 mA, and turning on the output with a 2.3 V red LED connected up. The LED is quite safe.

(https://www.eevblog.com/forum/reviews/tti-el302p-power-supply/?action=dlattach;attach=36351;image)
Title: Re: TTi EL302P Power Supply
Post by: grenert on January 10, 2013, 01:18:01 am
Thanks for showing us the data.  Are TTi power supplies sold in the US?  Are they still made in the UK?
Title: Re: TTi EL302P Power Supply
Post by: IanB on January 10, 2013, 02:31:06 am
Yes, on the back it says "Made in England". I got it new from Saelig.