Hi all.
I bought this 1500W 30A1800W 40A DC-DC Boost Converter Step Up Power Supply Module 10-60V to 12-90V adjustable voltage charger [boost]

https://www.aliexpress.com/item/400...o.order_list.order_list_main.5.5d091802jFZ5Gs

and a 48v-1000w switch power supply [power], and wire them up, the power measured good output 48V.

when connected boost TO power, power can't start up, and boost's under voltage indicator light flashing, I did few turns adjust on Input low cell protective regulation pot, turn on again heard two explosion and saw sparks in area A and B, and now power is on, boost output only 48v. what can be?

1. three fuse measured good;
2. can be one of the four capacitor blow out?

Thanks
Adam

POWER:


BOOST:




area A & B:

 

Where are areas 'A' and 'B' - I don't see them marked.
On the boost regulator the large inductor seems displaced from its matked location. Has it shorted to or damaged something by moving? It looks very close to the mounting screw on its left.

 

Is it possible you connected power backwards? If it was connected properly, the only thing I can think of is that the board was defective.

 

Where are areas 'A' and 'B' - I don't see them marked.
On the boost regulator the large inductor seems displaced from its matked location. Has it shorted to or damaged something by moving? It looks very close to the mounting screw on its left.

Thanks.
uploaded picture with area 'A' & 'B'.
The picture from seller, don't know why the inductor displaced, real board is ok.

 

Is it possible you connected power backwards? If it was connected properly, the only thing I can think of is that the board was defective.

thanks.
not that. there are text marker: IN+; OUT+;

 

thanks.
not that. there are text marker: IN+; OUT+;

That never stopped me from connecting things wrong!

 

The statements in post #1 are a bit confusing. The TS bought a mains powered DC supply able to deliver 1000 watts output, which at 48 volts out is just a bit more than 20 amps, 20.83 amps, to be exact. Also bought an 1800 watt DC to DC boost supply with NO specifications provided. We have no information about the specified input voltage or the current requirements. So I am going to guess that the intended input voltage was 48 volts. If the DC to DC supply were to deliver an output of 1800 watts, and if it were 100% efficient, the input current would be 37.5 amps. That is much greater than the maximum output current of 20.83 amps rating for the power supply.

The DC to DC 1800 watt supply was connected to the 20 amp 48 volt output of the mains powered supply. Eventually the DC to DC supply failed somehow, and now the 48 volts power passes thru, apparently.
To deliver the desired 1800 watts output the DC to DC boost supply would need to be almost 200% efficient.

That level of efficiency is greater than I can design a system to provide.

 

The statements in post #1 are a bit confusing. The TS bought a mains powered DC supply able to deliver 1000 watts output, which at 48 volts out is just a bit more than 20 amps, 20.83 amps, to be exact. Also bought an 1800 watt DC to DC boost supply with NO specifications provided. We have no information about the specified input voltage or the current requirements. So I am going to guess that the intended input voltage was 48 volts. If the DC to DC supply were to deliver an output of 1800 watts, and if it were 100% efficient, the input current would be 37.5 amps. That is much greater than the maximum output current of 20.83 amps rating for the power supply.

The DC to DC 1800 watt supply was connected to the 20 amp 48 volt output of the mains powered supply. Eventually the DC to DC supply failed somehow, and now the 48 volts power passes thru, apparently.
To deliver the desired 1800 watts output the DC to DC boost supply would need to be almost 200% efficient.

That level of efficiency is greater than I can design a system to provide.

Thank you MisterBill2.
1. the link in #1 is the boost board web, which actually included 1800w/1500w/1200/ group, and mine is 1500w that Step Up Power Supply Module 10-60V to 12-90V;
2. for input V=48v, maximum current is 30A‑35A; I guess the 1800w theoretically comes from here;
3. you are right, a 1000w power supply not possibly to provide a 1500w/1800w boost to a full output. for me they are the most close match parts I can get so.
question now is I don't even got a chance to test them, anyway, I bought another two boosts, I waite, but if I can't find the reason of error, fear to use new one.

 

Very interesting about getting more boost-switcher boards. The link said only one left in stock!
It is unusual to follow a power supply with another power supply in sequence. And I wonder if there was any load on the output of the boost supply. What is the intended output voltage? Boost supplies are a less efficient application of switch-mode technology.

What is the purpose of this system? I see quite heavy leads connected to the output of the boost supply, was any load connected at the time of this test???

Were there any any instructions or data sheets provided with either power supply?? I would not do business with any supplier that was not able or willing to supply any data with a product.
Without any additional information on that boost assembly my evaluation is that it is a totally unsuitable product for any application. The link to the boost supply did not mention that no data or specification, nor user information was provided.

 

Very interesting about getting more boost-switcher boards. The link said only one left in stock!
It is unusual to follow a power supply with another power supply in sequence. And I wonder if there was any load on the output of the boost supply. What is the intended output voltage? Boost supplies are a less efficient application of switch-mode technology.

What is the purpose of this system? I see quite heavy leads connected to the output of the boost supply, was any load connected at the time of this test???

Were there any any instructions or data sheets provided with either power supply?? I would not do business with any supplier that was not able or willing to supply any data with a product.
Without any additional information on that boost assembly my evaluation is that it is a totally unsuitable product for any application. The link to the boost supply did not mention that no data or specification, nor user information was provided.

1. there are many many links selling this kind of parts;
2. I bought two more try to use them in parallel if needed. if you mentioned in sequence mean the power + boost, I guess the power is almost fixed output supply, the pot is for fine-tuning only?
3. this unit is simply adjustable power, used to test dc motor kinds small stuff, there were no load when I did that test.
4. the boost web has quite detail info.; the power's seller can't find now, guess shop closed? it is similar but not same as:
https://www.aliexpress.com/item/1005006174217663.html?spm=a2g0o.productlist.main.1.758950318KKEp5&algo_pvid=e02d694b-904a-4ebd-9e93-be397c92dd11&algo_exp_id=e02d694b-904a-4ebd-9e93-be397c92dd11-0&pdp_npi=4@dis!CAD!119.06!92.87!!!85.19!66.45!@21032dcb17148590810516347e8dd1!12000036121690338!sea!CA!125738190!&curPageLogUid=2PXicQBr81KF&utparam-url=scene:search|query_from:
and this one is already come with two pots to adjust V/I. I may just buy this one?

 

The power supply listing in the link DOES NOT PROVIDE much information. Not enough information such as regulation capability, maximum operation temperature, the over-current protection scheme, or the output voltage noise and ripple. Go to the Digikey website catalog and look at the specifications and data for the power supplies that they sell.
Also, look at the specifications for the DC to DC supplies that they sell. THOSE are useful data sheets.

 

The DC to DC 1800 watt supply was connected to the 20 amp 48 volt output of the mains powered supply. Eventually the DC to DC supply failed somehow, and now the 48 volts power passes thru, apparently.
To deliver the desired 1800 watts output the DC to DC boost supply would need to be almost 200% efficient.

What makes you think he was trying to output more than the input power? He does not mention a load the boost converter. With no load there should not be a problem.

Adan: Was there a load?

 

What makes you think he was trying to output more than the input power? He does not mention a load the boost converter. With no load there should not be a problem.

Adan: Was there a load?

One property of high power output power supplies is that some of them also require rather high power inputs, which do not reflect the power delivered to the load. Some of those supplies are very inefficient at low loads.

AND, because nether we nor the TS have anything approaching adequate information about these boost regulators and how to adjust them, a destructive failure occurred.
There are three adjustments , and the one that broke it was "low-cell under voltage protection." Consider that function, and whatever it is actually intended to do is not at all clear. Output current regulation and output voltage regulation are fairly clear, this one is not at al clear. What do other guess that it might do???
Consider also that the boost regulator was not able to start because the power supply was possibly overloaded?