Today i got my 5 x power supplies from Ray Wu's store on Aliexpress (http://www.aliexpress.com/fm-store/701799/209855560-289599951/350W-Dual-Output-Switching-Power-Supply-88-264VAC-input-12V-350W-output-CE-and-ROHS-approved.html) It took from purchasing on a Tuesday night to delivering at my front door Monday morning, that's not bad service at all. As well Ray has great English skills, he is very helpful and you will be able to save a lot of money by dealing with him
I found that the packageing was not the best but sufficient for the power supplies.
I then proceeded to do a 1/2 hour 300 watt burn in test on each power supply using 4 x 12v 50 watt MR16 halogens and a 100 watt Hella spot light (these power supplies will not be running at 300 watts constantly during the show).
The power supplies showed that at 300 watt loading the DC voltage output voltage was 12.1 to 12.2 volts. The voltage regulation appears to be OK as well as it held 12.1 to 12.2 volts from no load up in increments of 100 watts. The voltage can also be adjusted on these power supplies if required.
The power supplies did get hot but were not that hot that you couldn't hold them. They have a fan installed on the units, so when there is a lot of loading on the PSU then the fan will run faster. This fan feature may need to be modified to stay full at full speed due to changing loads that will have the fan going up and down in speed.
The fans themselves look like the weak point in the power supplies, out of the 5 units i received i had 1 PSU where the fan ran for about 5 minutes before failing. This is no big issue for me as I will get another one from scraps and put it in and I will be opening them up so I can modify it so the fan stays full speed
Other observations with a couple of the transformers was when the 300watt load was attached and then the power supply was turned off and then back on this would cause the power supply to shut down on overload and then the PSU would not turn back on until the load was removed.
Based on my observations I am going to use these 350 watt power supplies and load them up to approx 250 watts each, I will also modify the fans so that they stay on constantly at full speed instead of being load driven. The price for 5 of these PSU's was US$130 delivered to the Illawarra NSW Australia. Even if i treat these power supplies as 250 watt instead of 350 watt and factor in that 1 unit is a spare, the value is still very good. You also give yourself the benefit of having a spare in case one fails. The value of shipping is much cheaper as well when buying multiple units. I know now where ill be getting my 5, 12 & 24 volt transformers from. All in all very happy and a hell of a lot cheaper than eBay and with quick delivery.
I found that the packageing was not the best but sufficient for the power supplies.
I then proceeded to do a 1/2 hour 300 watt burn in test on each power supply using 4 x 12v 50 watt MR16 halogens and a 100 watt Hella spot light (these power supplies will not be running at 300 watts constantly during the show).
The power supplies showed that at 300 watt loading the DC voltage output voltage was 12.1 to 12.2 volts. The voltage regulation appears to be OK as well as it held 12.1 to 12.2 volts from no load up in increments of 100 watts. The voltage can also be adjusted on these power supplies if required.
The power supplies did get hot but were not that hot that you couldn't hold them. They have a fan installed on the units, so when there is a lot of loading on the PSU then the fan will run faster. This fan feature may need to be modified to stay full at full speed due to changing loads that will have the fan going up and down in speed.
The fans themselves look like the weak point in the power supplies, out of the 5 units i received i had 1 PSU where the fan ran for about 5 minutes before failing. This is no big issue for me as I will get another one from scraps and put it in and I will be opening them up so I can modify it so the fan stays full speed
Other observations with a couple of the transformers was when the 300watt load was attached and then the power supply was turned off and then back on this would cause the power supply to shut down on overload and then the PSU would not turn back on until the load was removed.
Based on my observations I am going to use these 350 watt power supplies and load them up to approx 250 watts each, I will also modify the fans so that they stay on constantly at full speed instead of being load driven. The price for 5 of these PSU's was US$130 delivered to the Illawarra NSW Australia. Even if i treat these power supplies as 250 watt instead of 350 watt and factor in that 1 unit is a spare, the value is still very good. You also give yourself the benefit of having a spare in case one fails. The value of shipping is much cheaper as well when buying multiple units. I know now where ill be getting my 5, 12 & 24 volt transformers from. All in all very happy and a hell of a lot cheaper than eBay and with quick delivery.