Domestic supply to 4.5kw appliance.

[lolex]

Hi there,

 

My wife wants to buy a large (industrial) dehydration machine. She's gone into the 'fish business' and relying on the sun at this time of year is problematic.

 

I've had a look on the internet at the machine she wants to buy. They are rated 3.5 to 4.5 Kw.

 

I know very little about electricity, but I'm pretty sure that a standard domestic power supply and socket will not safely supply this amount of power. (Although maybe large air-conditioning units use this much).

 

Am I right ?  (It would be cheaper if I'm wrongl.

 

I guess we can get a local electrician to put in a new supply from the main switchboard  and a heavy duty power socket. What would we need to specify if that's needed?

 

Any ideas about the approximate cost?

 

Thanks a lot for your help...

 

 

[Crossy]

Yeah, you're going to need a dedicated >20A circuit, similar to what would be used for a bigger shower unit. Probably run in 4mm² cable on a 32A breaker. Shouldn't be beyond your local man.

 

If the beast has a plug you'll need a matching outlet.

 

What size meter do you have? (5/15, 15/45, 30/100).

 

[ukrules]

I will add to what Crossy said that it might be worth checking the size/ capacity of the cable between the house and the pole outside the house.

 

I had one that overheated and melted parts of an old breaker panel - the cable was so thin it was red hot.

 

We rewired it all the way to the pole with a better cable.

 

This happened with no aircons or shower units, just fridges, freezers but there were a few power eating deep fryers in the place.

 

Worth a check, we got away without a fire but I think we came close. The wiring we replaced might have been 30 or 40 years old.

[lolex]

14 minutes ago, Crossy said:

 

What size meter do you have? (5/15, 15/45, 30/100).

Thanks Crossy,

 

I'll try and find out what meter size we have.

 

I'm stuck in Australia, so it's a bit challenging...

* where on the meter is the 5/15 etc rating ?  

* Does it usually have any units after the digits eg A or W  ?

 

My wife's often quite good at finding this kind of thing...I remember her saying it was a larger size when she bought it.

 

Cheers !

 

 

 

 

[Crossy]

6 minutes ago, lolex said:

* where on the meter is the 5/15 etc rating ?  

 

It will be marked on the meter plate near the serial number. If not sure post a photo here (managing that from Oz could be a challenge in itself).

 

This is ours, a 15/45.

 

[lolex]

Thanks so much....that pic will help a lot !

[sometimewoodworker]

8 hours ago, lolex said:

My wife wants to buy a large (industrial) dehydration machine. She's gone into the 'fish business' and relying on the sun at this time of year is problematic.

 

I've had a look on the internet at the machine she wants to buy. They are rated 3.5 to 4.5 Kw.

Which machine are you looking at & what’s the drop in humidity over what period are you looking to get?

 

I ask as I have a dehumidifier that can certainly run from a regular supply, I am not bringing the humidity down by more than 15%~30% over 10 hours  but the room it’s in is quite large at 90 square metres and 540 cubic metres. It’s rated at 45 litres per day at 30^oC. For sure you will probably need something bigger but mine is rated at 700W so a dehumidifier at 3.5 to 4.5 Kw is probably for a very large scale business. 

[lolex]

On 6/27/2021 at 7:14 PM, Crossy said:

What size meter do you have? (5/15, 15/45, 30/100).

It's a 15/45 the same as yours Crossy. Hopefully that's big enough...

 

Looking forward to your further thoughts.

 

Cheers.... Mark

[Crossy]

Yours isn't steamed up inside like ours is.

 

4.5kW is about 20A at 220V so about 50% of your meter capacity, unless you have fryers/ovens etc etc it's likely going to be OK.

 

Quite likely it's not going to be running 100% anyway.

 

Could be an idea to add some solar power as well ???? 

 

[lolex]

20 hours ago, sometimewoodworker said:

Which machine are you looking at & what’s the drop in humidity over what period are you looking to get?

Hello StWW...

It's all a bit difficult...I'm stuck in Australia ... My wife buys around 200kg fish at a time...so the machine probably needs to cope with 40kg at a time. All the machines I've found on the internet are 4kw to 4.5 KW....although I'm sure there are others...

[lolex]

On 6/27/2021 at 7:14 PM, Crossy said:

Probably run in 4mm² cable on a 32A breaker.

Thanks again!

 

Will the 32A breaker be something to fit in the existing RCD Switchboard or do we use a separate (purposed) breaker?

 

I have no practical knowledge...but I think a separate purpose dedicated breaker would be better. (Don't want to overload the existing board that has 3 or 4 air conditioning units wired in.)

 

Here's a pic of the switch board.

 

[Crossy]

If you have a spare position which you could put a 32A then that will be fine.

[lolex]

The wiring from the meter to the switchboard will be 'strong enough' then? (To carry all the load that may be drawn from the switchboard)

[Crossy]

36 minutes ago, lolex said:

The wiring from the meter to the switchboard will be 'strong enough' then? (To carry all the load that may be drawn from the switchboard)

 

If it's reasonably modern then yes it will be fine.

 

You can check the cable size from the meter by looking at the labelling. Let us know what it says.

 

[sometimewoodworker]

1 hour ago, lolex said:

Hello StWW...

It's all a bit difficult...I'm stuck in Australia ... My wife buys around 200kg fish at a time...so the machine probably needs to cope with 40kg at a time. All the machines I've found on the internet are 4kw to 4.5 KW....although I'm sure there are others...

While 200kg is a reasonably sized quality I would have thought that the amount of water would be at around 140 litres,  depending on how quickly you need to exhaust this and what the target humidity you are aiming at will govern the size of machine machine needed.

 

For 40kg that’s only around 28litres so that’s inside the comfortable range for my unit

 

Mine is almost the smallest that the company makes though it does qualify as an industrial unit. I would contact the manufacturer directly they are https://www.utile.co.th/ they will advise exactly what you need.
 

But don’t forget that you will need to build a room that you are going to put the fish in. The dehumidifier is just one part of the equation. 

[SomchaiDIY]

26 minutes ago, sometimewoodworker said:

While 200kg is a reasonably sized quality I would have thought that the amount of water would be at around 140 litres,  depending on how quickly you need to exhaust this and what the target humidity you are aiming at will govern the size of machine machine needed.

 

For 40kg that’s only around 28litres so that’s inside the comfortable range for my unit

 

Mine is almost the smallest that the company makes though it does qualify as an industrial unit. I would contact the manufacturer directly they are https://www.utile.co.th/ they will advise exactly what you need.
 

But don’t forget that you will need to build a room that you are going to put the fish in. The dehumidifier is just one part of the equation. 

 

All fish process near our Rayong factory use electric heated cabinet with air blower to dry fish not room type dehumidifier

 

I think this is why large electricity supply is required for this process some cabinets are three phase many kw

[sometimewoodworker]

1 hour ago, SomchaiDIY said:

 

All fish process near our Rayong factory use electric heated cabinet with air blower to dry fish not room type dehumidifier

 

I think this is why large electricity supply is required for this process some cabinets are three phase many kw

That’s interesting and it certainly seems as if @lolex needs to check exactly what’s being suggested and used.