BIZARRE electrical question

[supertek65]

thanks printer!!

that makes sense to me!!!

if it is a piston or whatever they use in those little things!!!!!!!!!!!!!!!!!!!!!

Nothing special about it. Bet you could figure out why the current relationship once you realize it is not a centrifugal pump but a positive displacement pump.

[printer2]

Swash plate pump, bottom of page.

http://www.pumpmarket.co.kr/tecinfo-principle.htm


The image shown is the reverse of what the pumps are like. Rather than the body spinning the plate spins. They may have something like a ball bearing riding on the plate pushing on the piston rod. On the other side of the piston they may have a spring to return the piston when the swash plate spins and reduces pressure on the bearing. If I find a better image I'll post it later.

[supertek65]

i do not think i will ever work on one of those????????????

Swash plate pump, bottom of page.

http://www.pumpmarket.co.kr/tecinfo-principle.htm


The image shown is the reverse of what the pumps are like. Rather than the body spinning the plate spins. They may have something like a ball bearing riding on the plate pushing on the piston rod. On the other side of the piston they may have a spring to return the piston when the swash plate spins and reduces pressure on the bearing. If I find a better image I'll post it later.

[puttachai]

I'm a novice in HVAC, I want to clarify if my understanding is correct, regarding the formula

Power (hp) = (Pressure x flow) /(conversion factor x %eff)

Is the pressure here is the pressure different between inlet and outlet? and the flow here is volume/unit time? (because that will make the power unit J/s)

Also I want to clarify what is the conversion factor here means?

[supertek65]

power is watts

pressure is voltage

flow is amps current

and ofcourse 3 phase you multiply by 1.73

746 watts per hp

[madhat]

A) Get the motor rewound
B) Replace the motor
C) Buy American Kartcher, use German one for spare parts. "you'll always need parts"
D) Buy a voltage converter, which will cost more than a new Power washer. **

**Some Welders will put out 50Hz

[supertek65]

B




B

A) Get the motor rewound
B) Replace the motor
C) Buy American Kartcher, use German one for spare parts. "you'll always need parts"
D) Buy a voltage converter, which will cost more than a new Power washer. **

**Some Welders will put out 50Hz

[timebuilder]

Ding, ding, ding, ding!

Frank is correct!

[supertek65]

winner!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Ding, ding, ding, ding!

Frank is correct!

[joethemechanic]

Here in Philly we have a few spots that have what we call a "Bastard leg". It is actually a 240 volt leg and that's how they get 240 in some areas, You can test one of the legs to ground and you get 240 and on the other you get nada. Threw me for a loop when i first ran into it.
I used to do work for a high end french restaurant here in Philadelphia with a prestigious French chef. He used to try to get his equipment from Europe as he said he hated american equip. I just know there was something the electricians had to do with the stuff before it would work, when i remember talking to them about it they mentioned the 3 wire and 4 wire thing.
Boy nothing better then working on a reach in with French schematics and manuals

that is actually a transformer with a 4 wire delta secondary. it will be 3 phase 240 with a center tap in one of the windings to provide 120V single phase



YOU WILL FIND THAT THE HIGH LEG IS ACTUALLY 208 VOLTS NOMINAL TO GROUND

[joethemechanic]

oh btw, if you replace the motor with a 60 cycle unit, you are still going to be driving the pump too fast.

I am guessing this is most likely a 4 pole motor. That means it would have a synchronous speed of 1800 (less rotor slip) running on 60 HZ. If this unit was designed for 50 HZ operation the motor would have a synchronous speed of 1500 (less slip)

You can not get a 1500 rpm 60 HZ squirrel cage induction motor. You just can't have enough rotor resistance to allow that much slip without generating a whole lot of heat.

If this is a direct mounted pump you can either run it from a VFD, or change the motor to a higher HP unit in order to handle the increased torque requirements caused by operating at a higher head.

now if this is a belt drive pump, you could just change the ratio to get the pump speed back to design spec.

[madhat]

I was talking to someone at pressureparts.com and they said all you would probably need is a Bypass valve, to deal with the higher RPM and Pressure. The motor would run fine on 60hz, as long as the voltage was within range. You should call their 800 number and talk to a tech. with model and serial numbers handy.

[secorp]

I agree with madhatter call a pro!