compressor blowing my fuse

[markw]

hi pepes..and im new :-)

i have recently bought a 50l compressor...on start up its blowing my 6 amp fuse in my 20 amp main breaker...so im not sure what size fuse i need to run my 50l compressor i assume with a 20amp breaker i cant go over a 20 amp fuse...but im not quite sure even what size fuse i need to run my compressor or even if 20 amp will be ok....thanks in advance mark

 

[wilbur]

You may be better help if you post a picture of the rating plate on the motor of the compressor AND a picture of what you're calling your 'breaker'.

But a 6A fuse/breaker is unlikely to be enough to run a compressor much bigger than the one in your fridge.

 

[markw]

• Engine Size: 2.5HP
• Power Consumption: 1.5 kw
• Voltage: 230v @ 50Hz
• Rated Speed: 2580rpm
• Motor Poles: 2 P
• Air Displacement: 9.6 cfm
• Noise Rating: 97dB
• Discharge Pressure: 115psi / 8 bar
• Restart Pressure: 70psi / 4.8 bar
• Tank Capacity: 50l
• Air Outlet: 1/4"
• Product Dimensions: 700mm (L) x 390mm (W) x 710mm (H)
• Net Weight: 38kg

 

[markw]

• Engine Size: 2.5HP
• Power Consumption: 1.5 kw
• Voltage: 230v @ 50Hz
• Rated Speed: 2580rpm
• Motor Poles: 2 P
• Air Displacement: 9.6 cfm
• Noise Rating: 97dB
• Discharge Pressure: 115psi / 8 bar
• Restart Pressure: 70psi / 4.8 bar
• Tank Capacity: 50l
• Air Outlet: 1/4"
• Product Dimensions: 700mm (L) x 390mm (W) x 710mm (H)
• Net Weight: 38kg

 

[markw]

just to let you all know my compressor runs fine on my 30 amp house supply but i have to use an extension cable to run it in my garage which is not recommended by the compressor maker

 

[MoreWellie]

You do need to make sure how much current all the wiring that leads up to the compressor is capable of handling. Your switch is rated at 20 amps but the wiring itself needs to be rated accordingly

If the manufacturer has specified a particular supply requirement then you should follow their guidance.

I would expect a 2.5HP compressor to be able to run on a normal 13 amp plug but it would need a 13amp fuse fitting you might still find the plug fuse blows very occasionally when starting on cold days

The majority of small compressors are designed to be started using the pull up switch on the compressor itself and specifically say not to start it by just turning the mains supply on and off

I am guessing you got to 6 amps by using the 1.5Kw figure but this is the running consumption and it needs a much higher current to start the compressor which is why the fuse is blowing

 

[slim_boy_fat]

@markw Hopefully you've got your answer above ^^ , but I just wanted to say welcome

 

[Exuptoy]

It's not a 20amp breaker, its 20amp switch or probably fused switch, as said above the compressor would probably have been fused at 13a in the plug top.

You say you're blowing 6a fuse? Is this fuse inside the switch you have photographed?

A fuse should be rated to protect the cable. If a circuit is run to feed a lighting circuit or similar and fused at 6amp then the cable will probably only be rated to carry around 6amps. That will be why its fed with a 6amp fuse.

It's not clear from your pic if the socket above is fed from the switch? If it was then the cable to the socket should be fed in 2.5mm cable, in which case it would carry the 13a required and could be fed with a 16amp fuse wire.

 

[markw]

ill take some more pics but thanks so far..the 6 amp fuse is in the breaker i have took a pic of ..when it blew i just put another NITD6 fuse back in...it has a 13 amp fuse in the plug that came as standard when i bought the compressor

 

[markw]

pics as promised

 

[markw]

more pics

 

[markw]

last one..hope these help :-) my socket seems to fed from the mini breaker

 

[Exuptoy]

It looks like the cable feed from the switch fuse is at least 2.5mm therefore it should carry 20amps comfortably. Firstly I'd check the armoured cable to the breakers has writing around the insulation showing 3x2.5mm and you'll be god to go, then I'd change the 6amp fuse for a NIT20 fuse and swap out the MCBs for 16amp. You're existing set up asides from not allowing you to run anything over 6amps, doesn't allow for discrimination which means the tripping curve of a fuse wire is a different tripping time curve for an MCB so your fuse is blowing before the overload rating of the breakers. You're unlikely to be using everything that's plugged in at the same time and aside from the initial surge on start up you compressor so that won't be pulling 13amps all the time anyway.
I take it the 6amp MCBs are feeding the sockets? If one is feeding lighting then leave that at 6amp and just change the socket one for 16amp.

 

[markw]

@markw Hopefully you've got your answer above ^^ , but I just wanted to say welcome

 

[markw]

It looks like the cable feed from the switch fuse is at least 2.5mm therefore it should carry 20amps comfortably. Firstly I'd check the armoured cable to the breakers has writing around the insulation showing 3x2.5mm and you'll be god to go, then I'd change the 6amp fuse for a NIT20 fuse and swap out the MCBs for 16amp. You're existing set up asides from not allowing you to run anything over 6amps, doesn't allow for discrimination which means the tripping curve of a fuse wire is a different tripping time curve for an MCB so your fuse is blowing before the overload rating of the breakers. You're unlikely to be using everything that's plugged in at the same time and aside from the initial surge on start up you compressor so that won't be pulling 13amps all the time anyway.
I take it the 6amp MCBs are feeding the sockets? If one is feeding lighting then leave that at 6amp and just change the socket one for 16amp.

yay thanks so much this is what i had worked out but just needed it confirmed

 

[markw]

now i cant buy an old mem type 2 as they are obsolete...nowt goes easy does it :-)

 

[angellonewolf]

ebay normaly plenty old stuff on there

 

[Exuptoy]

Most of the time other stuff fits anyway. Google it.

 

[brightspark]

there only din rail mounted in an enclosure. any make of breaker will fit providing u get a couple of the same make. they don't need to be double pole either .single pole be ok u have the 20 amp isolator for it