Lab power supply - which of these would you pick?

[radian]

That Sorensen is actually Thurlby EL302R. http://www.tti-test.com/products-tti/pdf-brochure/psu-elr-exr-series-7p.pdf. Should be very good power supply.

Wow, I didn't know Sorensen was into re-badging too... that's a bit odd. I guess it can be expected, maybe there isn't much incentive to design power supplies from scratch.

[staxquad]

Does it really need 480W input for that, or is that just the listed power input? Those often seem to be quite pessimistic.

No. I have a HP6002A and it doesn't need 480W input for sure. It is a very efficient power supply which uses several windings for different ranges of output voltages / currents. It says 600VA max. on the rear but you can't thumb-rule that to Watts.

Agilent has the 480Watts printed in the manual and the 600VA is printed on the rear of the unit.   It's Agilent's specs.

600VA AC = 480Watts,  if the power factor is .8 

The 600VA tells the user what fuse to use while 480 Watts tells the user what input power is being used.

Have you ever checked with a watt meter the input power required on your unit to output 200 Watts, or are you just guessing?

[nctnico]

Does it really need 480W input for that, or is that just the listed power input? Those often seem to be quite pessimistic.

No. I have a HP6002A and it doesn't need 480W input for sure. It is a very efficient power supply which uses several windings for different ranges of output voltages / currents. It says 600VA max. on the rear but you can't thumb-rule that to Watts.

Agilent has the 480Watts printed in the manual and the 600VA is printed on the rear of the unit.   It's Agilent's specs.

600VA AC = 480Watts,  if the power factor is .8 

The 600VA tells the user what fuse to use while 480 Watts tells the user what input power is being used.

Have you ever checked with a watt meter the input power required on your unit to output 200 Watts, or are you just guessing?

I didn't but dissipating 280W with the internal heatsink assembly seems very unlikely. It would be silly for any power supply to dissipate more than the output load. IMHO the 480W figure is a misprint. You could check the service manual for the voltages and do the math based on the output voltage. Maybe add 30W for the internal electronics and transformer losses.

About the Chinese power supplies: they may not be excellent but the problem with the HP supplies is that they are huge boatanchors. I'm thinking about buying the 36V /3A version of this power supply:
http://www.manson.com.hk/en/dcpowersupplies_detail.php?m=3&id=16

For some reason I usually end up using the power supply I made in school 20 years ago. I guess the low weight and small size make it ideal to move it around. My HP6002A OTOH is very large and heavy and has a noisy fan (I did make it temperature controlled though).

[radian]

Between Agilent and Tektronix, which has a better reputation for quality power supplies?

[wraper]

I can say that you shouldn't worry about Agilent, Tektronix and Thurlby (Sornensen). They all are very decent manufacturers. And quality of their supplies are overkill for you considering that you were going to buy china crap for less than 60 bucks. You can pick any of them that gives you required voltage and current ranges. Agilent makes some ultra low ripple supplies but you will get more volts/amps from Thurlby for the same price. I would go for Thurlby, you will get more for the same buck.

[staxquad]

Does it really need 480W input for that, or is that just the listed power input? Those often seem to be quite pessimistic.

No. I have a HP6002A and it doesn't need 480W input for sure. It is a very efficient power supply which uses several windings for different ranges of output voltages / currents. It says 600VA max. on the rear but you can't thumb-rule that to Watts.

Agilent has the 480Watts printed in the manual and the 600VA is printed on the rear of the unit.   It's Agilent's specs.

600VA AC = 480Watts,  if the power factor is .8 

The 600VA tells the user what fuse to use while 480 Watts tells the user what input power is being used.

Have you ever checked with a watt meter the input power required on your unit to output 200 Watts, or are you just guessing?

I didn't but dissipating 280W with the internal heatsink assembly seems very unlikely. It would be silly for any power supply to dissipate more than the output load. IMHO the 480W figure is a misprint. You could check the service manual for the voltages and do the math based on the output voltage. Maybe add 30W for the internal electronics and transformer losses.

About the Chinese power supplies: they may not be excellent but the problem with the HP supplies is that they are huge boatanchors. I'm thinking about buying the 36V /3A version of this power supply:
http://www.manson.com.hk/en/dcpowersupplies_detail.php?m=3&id=16

For some reason I usually end up using the power supply I made in school 20 years ago. I guess the low weight and small size make it ideal to move it around. My HP6002A OTOH is very large and heavy and has a noisy fan (I did make it temperature controlled though).

Aligent specs stand, until proven wrong though testing, not opinion

It would be convenient if every time you didn't like distortion or ripple specs that you'd just say it was a printing error 

[Monkeh]

Aligent specs stand, until proven wrong though testing, not opinion

Just because it says 480W maximum input power, doesn't mean it ever actually requires 480W to output 200W. That could easily be an inrush specification.

[alm]

Between Agilent and Tektronix, which has a better reputation for quality power supplies?

Tektronix makes power supplies? Apart from a few TM500 plugins in the seventies, all of the Tektronix power supplies are rebadge jobs as far as I know.

[N TYPE]

Guys what do you think about this Dual Tracking Linear Power supply kit http://www.altronics.com.au/index.asp?area=item&id=K3218 which was first featured in silicon chip magazine http://archive.siliconchip.com.au/cms/A_112014/article.html I'm sure I can make my own for cheaper than the price listed here as I have the schematics, parts list and board templates already, The thing which I like is that its dual tracking, and as it's a kit I can add extra outputs or modify the existing circuit to suit. Sorry I cant post the entire article as I dont have permission but the specs are as follows:
Output voltage : +- 0-19V
Output current : up to 1.6A (With current limiting feature)
Noise (0-1A) : <5.25uV peak to peak
Ripple (0-1A) : <1mV RMS <1.7mV peak to peak

[M0BSW]

 I can only speak for what I have it's old it's calibrated its a Farnell D30  2, a vairiable volts  & amps bench power supply up to 30 volts can push up to 31.5, and Amps are 2A, and a readout, for me it's perfect. , and there fairly cheap on E-Bay, if you don't mind a 20 Year old supply.

[Cerebus]

The HP6002A 480W is kind of odd. I've never heard of inrush being speced like that, but who knows

If someone owns one put one of those 10 buck KillAwATT meters on it and load it. I think it must be a typo or something.

I know I'm reviving a very old thread but I came across this when I was considering bidding on an HP6002A and did a search on here for some background info. Long story short -  I now have an HP6002A and I thought that I'd close the loop by making some actual measurements and posting them.

So:

One HP6002A attached to a 2 ohm load, voltage set to 20V and current limit to 10A - both checked with my trusty old Fluke 25. Thus output power 200W +/- 0.85%. Input power (indeed measured with a cheap plug-in power meter) 375W and 455 VA. So that's 175W being blown out of the back by the fan. This is not however the maximum output power of the supply, just the limit of its in-regulation output. The manual states that it can safely run quite some way outside the regulation envelope and indeed the front panel has an 'overload' light to tell you when you are doing so. Thus it's quite possible that it could run to another 105W of input power. I don't have a lower resistance load that I could safely throw more than 200W into, so that thesis will have to remain untested for the time being.

By the way, the input power with no output load is 39W (69 VA). I suspect that at least 10W of that just goes into spinning the big-ass fan.

[eKretz]

Sorensen is great gear. They are owned by the same parent company as Ametek and Elgar. Those are also very good power supplies. I have a 1200 watt Sorensen switcher - it's been fantastic. Ripple on mine is about 5mV, not terrible.

[Pheadrus]

I know this is a very (very) old thread now, but it is still relevant and was one of my resources in researching these Chinese bench supplies prior to buying one last week.

Further to Cerebus, and in the interest of coming full sphere, I thought I'd put up my measurements taken of this 30V 0-5A "Hyelec HY3005ET" courtesy of Ebay for the princely sum of £34.88 ($43.50) all in. All measurements are taken using a Pico 3423 USB scope and a Pico TA009 current clamp.

Open circuit voltage display vs actual:
3.28V is actually 3.30V
11.97V is 12.00V
19.95V is 20.00V
29.94V is 30.00V

Displayed voltage vs current and ripple measurements taken:
3.30V / 5W5.1R resistor: displays 0.647A = 0.665A  31mA/278mV p-p
5.00V / 5W5.1R resistor: displays 0.982A = 1.011A  45mA/192mV p-p
5.00V / 5W10R resistor:  displays 0.507A = 0.510A  45mA/225mV p-p
12.00V / 10W20R resistor: displays 0.613A = 0.629A  62mA/256mV p-p
15.00V / 5W47R resistor:   displays 0.321A = 0.327A  36mA/267mV p-p
5.00V / 2x100W1R resistor:   displays 2.26A = 2.30A  131mA/299mV p-p
10.00V / 2x100W1R resistor: displays 4.20A = 4.24A  143mA/331mV p-p
Max V / 2x100W1R resistor: displays 5.086A = 5.219A  202mA/587mV p-p

There are no discernible voltage spikes no matter how much I mess with the power button or pull out/plug in leads with/without a load and voltage present. The most I saw was 15.07V for 0.4ms upon powering on with 15V equivalent dialled in and a 10R load connected.

The 80mm fan on the back seems to be speed controlled against the output voltage regardless of current. It becomes audible at 12V. There is a slight noise with a very low CC (<0.3A), sounds like faint radio squark, and again around the 5A range, nothing that a computer under the desk can't beat.