How many 1000 watts HPS have you had in a 25 kva transformer?

How many 1000 watts HPS have you had in a 25 kva transformer? the house main breaker is 150 amps.

I would like to know if it is possible to have 12 connected.

Thanks in advance.

you need to look at all the loads

at 230V youre only about 6A per light so depending on your loads youre getting up there, 12 should be fine if you dont have any other big loads like compressors, well pumps, massive AC units etc.

im guessing with 12HPS you do have massive AC units as well. if youre tight on power would be better to replace 12K of HPS with 8K of LED and cut your AC load nearly in half

augusto1 said:

How many 1000 watts HPS have you had in a 25 kva transformer? the house main breaker is 150 amps.

I would like to know if it is possible to have 12 connected.

Thanks in advance.

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A 25kva transformer can carry 80% load. If you are running 240v you will get 10k amps so ten is max eight is recommended twelve is too many. At 120v you can run sixteen max. To get amps divide the kva/v you get amps.

augusto1 said:

How many 1000 watts HPS have you had in a 25 kva transformer? the house main breaker is 150 amps.

I would like to know if it is possible to have 12 connected.

Thanks in advance.

Click to expand...

at 12,000 W, you are at "roughly" 1/2 of the capacity of the transformer. That's 100 amps of load at 120V. That's 2/3 of your main capacity (if the 150A is 120V), leaving only 50 amps for the rest of the house. Magnetic ballasts will be more reactive than digital ballasts and have a lower power factor, causing the transformer to "see" more kVA power than you are actually consuming. The answer is "maybe" depending on the rest of the load and what the overall power factor is at the transformer.

VegasWinner said:

A 25kva transformer can carry 80% load. If you are running 240v you will get 10k amps so ten is max eight is recommended twelve is too many. At 120v you can run sixteen max. To get amps divide the kva/v you get amps.

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How can I run more (sixteen) on 120v than (eight) on 240v? isn't it the same load?

Thanks in advance.

nfhiggs said:

at 12,000 W, you are at "roughly" 1/2 of the capacity of the transformer. That's 100 amps of load at 120V. That's 2/3 of your main capacity (if the 150A is 120V), leaving only 50 amps for the rest of the house. Magnetic ballasts will be more reactive than digital ballasts and have a lower power factor, causing the transformer to "see" more kVA power than you are actually consuming. The answer is "maybe" depending on the rest of the load and what the overall power factor is at the transformer.

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There are 240v at the main breaker, the transformer is a green square box located on my neighbour backyard floor.

Thanks in advanced.

CobKits said:

you need to look at all the loads

at 230V youre only about 6A per light so depending on your loads youre getting up there, 12 should be fine if you dont have any other big loads like compressors, well pumps, massive AC units etc.

im guessing with 12HPS you do have massive AC units as well. if youre tight on power would be better to replace 12K of HPS with 8K of LED and cut your AC load nearly in half

Click to expand...

I being thinking about to go with LED but I want something that I can install as same height (7' to 8') as a 1000 watts hps bulb, 1000w / 240v = 4.2 amps.

Thanks in advance.

augusto1 said:

I being thinking about to go with LED but I want something that I can install as same height (7' to 8') as a 1000 watts hps bulb, 1000w / 240v = 4.2 amps.

Thanks in advance.

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sure. so use big ass cobs, 100-200W each, reasonably close together. (4) 200 W cobs will beat any HPS in yield, coverage, and penetration

CobKits said:

sure. so use big ass cobs, 100-200W each, reasonably close together. (4) 200 W cobs will beat any HPS in yield, coverage, and penetration

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1)Which cobs can be run 100-200 watts?
2)Do you sell them?
3)What will be the materials list to build them?

Thanks for all your helps, I really appreciate it.

augusto1 said:

How can I run more (sixteen) on 120v than (eight) on 240v? isn't it the same load?

Thanks in advance.

Click to expand...

because 240v is twice as many volts as 120v generating power more efficiently than 120v .240v x 15A = 3600W 120v x 15A = 1800W half as much power so twice as many needed at 120 than 240, . If you are running 120v you are not getting the benefit of the transformer in the first place. A transformer can be center tapped, for 480v, and 240v and quarter tapped for 120v. I would recommend you hire an electrician to help you size your transformer and determine the proper panel allocation.

In the past, on 25kva design, I would design towards 240 system, and determine loads that way, most efficient. After that, I would determine my 120v loads and quarter tap those from a 240 center tap to a quarter wave and get 4 120v legs with equal power to a 120v panel, run the other half of the panel on 240v and run motors, and other large devices on the 240v side and run small electronics on the 120v side.

As others have stated, you need to determine total load, because you are creating heat and you will need ventilation, cooling, humidification, so most likely you will need a 400A main electrical panel, with 240, and 120 breakers for AC, and fans, and 120 breakers for lights, timers, water pumps, etc.

Probably the most you will get is 8 1000w HPS lights on a 25kva transformer

augusto1 said:

There are 240v at the main breaker, the transformer is a green square box located on my neighbour backyard floor.

Thanks in advanced.

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That transformer is for more than your residence. That transformer is being shared. you are going to have to contact the electric company to find out how much available power is left on that transformer, unless it is private owned and installed and then you will have to ask your neighbor, otherwise you will have to install your own transformer, about $15k