In Ingredible edger you can use wheels up to 2 inch size. As I am living in country where we have 50Hz electrical network, I am loosing 20% of the speed compared to 60Hz network.
Slightly off-topic, but an electrician who worked on a lot of motors, especially sub-pumps, told me that it is very important to match the voltage and frequency that feeds a motor to the motor's spec.
If you don't, the motor windings may get very hot, and burn out.
Anyway, it may be worthwhile to get the frequency adjuster installed sooner than later. But make sure it creates a sinusoidal voltage and current output at full load - harmonics pump extra electrical energy into A/C motors, which is partly dissipated as heat rather than producing mechanical power - and 5th harmonics typically produce a reverse torque in A/C motors, which fights the rest. I don't know how you check for sinusoidal output, but he when he wasn't trying to be fancy, he verified that a mean-responding current meter, and an rms-responding current meter, gave the same result.
I'm not an expert in this, and he was only an electrician, not an engineer, but this is what I vaguely recall he said:
It has something to do with how long the motor stays in "start mode". In particular, A/C motors, like fluorescent lights, when they start up, typically draw a lot of extra current. I don't know all the details - e.g., whether there is always internal circuitry, or whether it is sometimes a natural result of induction, etc.
(In addition, an A/C motor is to an extent a rotating inductor. It's impedance creates a different resistance to current flow at different speeds. E.g., when power companies create summertime "brown outs", lowering the voltage because they are near their maximum power output, he said he found that power draw by the University actually increased - probably because air conditioning motors draw more average power at lower voltage. However, he said it might "work" a little over the long run, because a lot of those air conditioners burned out, because the motors got too hot.)
There were other factors which influenced that, like alignment between the motor and pump, the mount positions within the range of travel of the linkages, motor and pump balance (most electricians are not trained as mechanics, yet are often told to maintain or replace motors), various ways of reducing startup water pressure on the pump (never put pumps in series to increase pressure - let each pump push water up to a well at atmospheric pressure instead; drill a pin hole into outflow pipes a foot or so over the outflow), proper lubrication, poor electrical voltage/current conditioning (such as harmonic components from switching power supplies, such as are in computers and UPSs), the incorrect wiring diagram that came with some motor control systems that used A/C for power and D/C current for control on the same line (half the diagrams left out the diode), inappropriate transformers, insufficiently large wires (creating voltage drops), the discrepancy between code current ratings (American motor companies do not rate motors by their mean or maximum current draw. They rate them by the size of the "overload breaker" that should be used to prevent burn out if the motor overheats for any reason. Most electricians don't know that. As with other appliances, they over-rate the breaker by at least 25% (I think), so the windings burn out before the breaker reacts.), the University's tendency to go with the lowest bidder (
), and other things.
When he started working at the University of Maryland, which had over 200 buildings with sub pumps, some of the sub pumps would fail every few weeks. Once he figured things out, by a combination of trial and error plus having discussions with the better motor shops, a master plumber, and the engineers who designed the motors and transformers, all of the motors he had installed within the past 30 years were still working. So these kinds of things, including voltage and frequency, may make a significant difference.
Obviously you should use a transformer if your voltage is off by more than a few percent.
It is common for low end motor shops to compensate for minor voltage and frequency differences by shortening the wire in the windings. That increases the current, which overheats the wire, and the motors don't last long. A rule of thumb used by the shops that maintained motors with fewer problems was that you should simultaneously increase the size of the wires used in the windings, so that the total mass of the metal was about the same.
He was once given a Japanese motor to install, with a very high reliability rating, designed for a different voltage and frequency, to install, that had been bought at a a discount. The buyer was very proud; he thought he was saving a lot of money, and was buying quality. It fell on the electrician I knew to prove him right. The electrician had an "unlimited master's license", and had no trouble finding a transformer to compensate for voltage. But he had to get together with a high end motor shop to re-engineer the motor. In the long run, it would have been much cheaper to use an American motor designed for American voltage and frequency.
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