Question 1

what is horse power rating of motor

Accepted Answer

There's an easy way to calculate the power of an electrical motor. First you multiply the volts times the amps to find the total power in watts, in this case 120 volts times 13.5 amps equals 1,620 watts. Next, you figure in an average 85% efficiency for electric motors to get 1,377 watts. (It's fair to assume this low-cost AC appliance uses a typical AC induction motor which is probably more like 80% efficiency, and the manufacturer doesn't claim anything better, but let's give them the benefit of the doubt since there are some electric motors that exceed 95% efficiency.) Then, you consider that you'll always be using this while plugged into an extension cord. Let's say it's the typical $30 14 gauge, 50 foot cord that's common (but be aware that longer or shorter cords, or higher or lower wire gauge, will change this) and factor in another 3% drop in power, so you have  1,335 watts at the machine.Now, 1335 watts is about 1.8 horsepower. If you're comparing this to the popular Mantis 16 inch tiller, with a 4-stroke Honda GX35 gas engine, that has 1.3HP at 7,000rpm. So on paper, this is 38% more powerful, but there are lots of other differences. It has a very different tine shape, but of course caring for a gas engine and getting virtually unlimited portability, vs. a maintenance-free electrical motor while tied to a power cord, are also big differences. TL,DR: This is more powerful in most cases than its gas competitors, and that's important but it's not the only consideration.

Question 2

has anyone compared the 12 amp model to the 13.5 amp one? is it worth spending the extra money to get the 13.5 amp tiller?

Accepted Answer

Our soil here in Montana has a lot of clay and turns rock hard when dry.  I have the 13.5 but to keep it from dancing all over the place I put a fifty pound lead weight on it to hold it down.  With the extra weight it does a great job

Question 3

Is 13.5 amps too much for a 15 amp circuit?

Accepted Answer

You will be fine on a 15A circuit.  Recommendations from the manufacturer are 14/3 (14gauge 3conductor) extension cord for up to 50ft and 12/3 extension cord for up to 100ft.  Total length should not exceed 100ft however I'm sure a 10/3 extension cord would be fine for more than 100ft but a 10/3 extension cord would be very expensive.  Please be aware that the tiller pulls the most current with the tines are digging deep in the soil and the motor is bogging down and under extreme strain it's possible it might pop the breaker on a 15A circuit.

Question 4

Can tines be removed for narrower tilling area?

Accepted Answer

yes, but...the tines are an assembly of 3 held to the shaft with a through bolt.  If you removed one assembly you could till with just one side, but the tiller is still over a foot wide and the empty shaft is still sticking out even without the tines.  this is a powerful machine, I would look at a lighter, narrower tiller if you want to do a more narrow area.

ASIN	B01DTIC79Q
Brand	Sun Joe
Colour	Black
Customer Reviews	4.6 4.6 out of 5 stars (15,357)
Enclosure Material	Alloy Steel
Global Trade Identification Number	00343538914303, 00810829024718
Item Weight	27.08 Pounds
Manufacturer Part Number	TJ604E
Model Number	TJ604E
Number of Items	1
Operation Mode	Electric
Power Source	Electric
UPC	343538914303 702872674623 343538916345 343538367659 810829024718 343538293514

Sun Joe TJ604E 16-Inch 13.5 AMP Electric Garden Tiller/Cultivator

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