Hookup For L1 L2 For A 1&1/2 Hp Franklin Bore Pump

[Beardog]

I hooked up the borehole franklin 1&1/2 hp pump with what I thought was L1 & L2 & I noticed 2 days ago after running the pump continuously for an hour to an hour & a half the ceramic portion of the knife switch is heating up over 40+ degrees. Is it possible that if it is hooked up with the 2 poles reversed it would make it hot when used. The switch will be a consumer panel when my neighbor finishes building. I think it is hot enough to pop a switch on a consumer panel. It was live on the left side(till an Lory truck full of dirt snagged the lines & I am not sure the hooked it up the same as it was. It goes from the main lines to the knife switch(large one) & then to the pump. the 3 leads to the pump are properly installed.

Any ideas on this issue? Edit: the wiring is 2 25 mm aluminum cable if that makes any difference.

Thanks Barry

Edited March 31, 2010 by Beardog

[longball53098]

Beardog, did you look to the Franklin web site for the model of pump and motor control. They really have good info there and I feel certain you can see a installation manual and wiring diagram for the units you have there

[Beardog]

Beardog, did you look to the Franklin web site for the model of pump and motor control. They really have good info there and I feel certain you can see a installation manual and wiring diagram for the units you have there

Will have a peak. the diagram for hookup is on the control box but I haven't tested the mains fro live & neutral yet.

[longball53098]

I see you edited the OP and added that the cable is aluminum and 2 25mm size? Is that 2.25 square mm? If the wire used is aluminum 2.25mmsq then I think it is too small for the load.The Franklin owners manual specs for the 1.5 hp pump that using copper cable number 12awg (3.31mmsq) the maximum distance in feet from the service to the motor should not exceed 360 feet or 108 meters.

From the manual:

Sizes given are for copper wire. For aluminum wire, go two sizes larger. For example, if table lists #12 (3.31mm squared) copper wire, use #10 (5.27mmsquared) aluminum wire.

[Beardog]

I think the distance exceeds the 108 meters by 4 times as much. the cable reads size 25 sq. mm X 2 cables.

I think that answers the heat question. It isn't enough to trip the internal breaker in the box- but in 3 weeks Colin will hook it up more permanent & will have to consider copper for the run.

Thanks again Longball

Barry

[elkangorito]

Beardog, aluminium cable is not a good idea. One possible reason for your 'outdated' knife switch heating up is due to a resistive connection created by corrosion (electrolysis).

When connecting aluminium to other metals for electrical purposes, it is very wise to find out which metals should not be used.

Another reason is that the switch is faulty.

It is not easy to assess this situation over the internet.

[Beardog]

I was wrong on the length of cable. The distance from the meter to the temporary drop pole is 160 meters + I think it is a 10 meter pole. Elk do you think if I made the line copper from the upper lines to the 10 meter drop the resistance being less with copper will make the knife switch cooler? It will be switched over to full copper in 3 weeks or so & it won't torch since it is just running a bit hot. Most it will do is melt one of the contacts.And with hot season over in 4-6 weeks the water will be used 1/4 of the time-most of it goes to 3 gardens. The house hardly draws any amps & it is a 30/100 service meter I had put in.

Thanks!

[david96]

If you have the full load current in amps on can calculate the voltage drop and hence the correct cable size in copper in sqmm.

The switch should be able to carry the full load of the motor continuously. You should replace the switch if possible and fit an MCB in place of the knife switch, 20Amp may be sufficient.

[Beardog]

Cool I will look for a 20 amp MCB & replace the drop from the pole with copper to the MCB & that should take the excess heat down. Thanks for the tip!

Barry

[longball53098]

There seems to be more discussion on this topic so I took the time to scan in the User manual pages that I have with my pump. Beardog said this was a 1.5hp pump so if it is the common Franklin most borehole drillers use it should be included in this info.

I scanned in the brochure and user manual pages and I think most of the info is readable.

I tried to shrink the original down more but then it became too hard to read.

FPS4400.pdf

[Beardog]

Thanks for the download . That will make it easier than waiting for Colin to bring over the manual.

Thanks again Barry

[elkangorito]

I was wrong on the length of cable. The distance from the meter to the temporary drop pole is 160 meters + I think it is a 10 meter pole. Elk do you think if I made the line copper from the upper lines to the 10 meter drop the resistance being less with copper will make the knife switch cooler? It will be switched over to full copper in 3 weeks or so & it won't torch since it is just running a bit hot. Most it will do is melt one of the contacts.And with hot season over in 4-6 weeks the water will be used 1/4 of the time-most of it goes to 3 gardens. The house hardly draws any amps & it is a 30/100 service meter I had put in.

Thanks!

Beardog, there is more to this than meets the eye. Is this pump supplied DIRECTLY from the KWH meter?

Firstly, the length of the cable run is required. Your following post (quoted below) indicates a length of about 450 metres (about 1,500 feet). Is this correct?

I think the distance exceeds the 108 meters by 4 times as much.

Secondly, the amount of current drawn by the pump must be known.

Thirdly, using an 'online' voltage drop calculator may not be accurate (please don't use such a thing) as voltage drop is subject to:

a] the current running through the cable (this is the key figure).

b] the type of cable used.

c] how the cable is installed (underground etc).

The Knife switch that you currently have, will most likely have some sort of fuse 'built in' to it. I'm glad that you are happy to replace this thing.

In other words, more information is needed to ensure that you DO NOT have a potential problem.

Edited April 2, 2010 by elkangorito

[Beardog]

Hi Elk.The drop line from the klw meter is Thw-a size 25 square mm. We used copper for the run originally but the copper thieves bagged our line & we had to put in aluminum as it is not worth stealing. It is 150 meters from the meter + 10 meter or so from top of the power pole to the knife switch. It is all above (not buried in the ground)It has now less than 1 meter of 2.5 romex wire going to the control box. the pump is 50 meters or so way from the control box. The supply is single phase 30/100 service & the transformer is about 50 meters away from the drop. Everyone else is either on a 5/15 or the next size up. Very few people on the line & we have the top size hookup.

The pump is a 1.5 hp I think it is the 1.1 kw rating.

max.input(sf load)5.1 amps 1600 watts line resistance5.9-7.2 locked rotor amps 20.8 fuse size 15 amp dual element 6.0

The house elecricity only uses at a given time a microwave- tv 32 inch- computer 850 watt power supply a 16" hatari fan. & up to 4 32w flourecent lites + 2 outdoor40w. bulbs a 2 burner inductive stove& 2 pumps a mitsubishi 205 & a 300 (which are rarely all on at the same time) No air no hot water no oven no wash machine. so the consumption is super low with the (camp house we built before we go ahead with the real one. That will have more conveniences & will draw more for sure! I hope this helps

Thanks

Barry

[david96]

What we have is a submersible pump motor rated at 220V 5.1 A full load current with a route length of 50 metres from an existing switch fuse unit rated at 20A. Run is underground.

The consumers mains commence at the meter with 25sqmm Al conductor. This would have an approx current rating of 16sqmm copper.

We will allow 2% for voltage drop in the 25sqmm consumers mains. this leaves 3% for the pump motor circuit.

The circuit may be run using 2.5sqmm minimum copper from the switch to the pump. A 20A MCB for protection, preferably an 30ma 20A RCBO.

( Calculations based on AS3000 )

[Beardog]

What we have is a submersible pump motor rated at 220V 5.1 A full load current with a route length of 50 metres from an existing switch fuse unit rated at 20A. Run is underground.

The consumers mains commence at the meter with 25sqmm Al conductor. This would have an approx current rating of 16sqmm copper.

We will allow 2% for voltage drop in the 25sqmm consumers mains. this leaves 3% for the pump motor circuit.

The circuit may be run using 2.5sqmm minimum copper from the switch to the pump. A 20A MCB for protection, preferably an 30ma 20A RCBO.

( Calculations based on AS3000 )

Thanks David I replaced the 2.5 romex with size 6 to take down a lot of the resistance till Colin does a permanent hookup using the right gauge wires for the run. oddly enough by putting in larger gauge wire from the (still the knife switch ) it cut the heat problem down by about 60% It is acceptable till he replaces with the right lines. If he lags more than 2 more weeks I will get a miniature circuit breaker & change out the outdated knife switch.