GE2800 Photos

[potatochips]

Pump performance curve

Since GE didn't provide us with a HP rating on any of the motors, it will be hard to tell how efficient these motors truly are. Although we can hook up an ammeter to see current draw during washing, we will never know the real efficiency. Centrifugal pumps draw more amps as you get to the top end and bottom end of the performance curve. And depending on how steep the curve is, there may be a narrow window where flow vs amp draw is most efficient. Im curious to know how efficient the SP motor is especially since it waivers in output speed as water is introduced and normal washing happens.

Next time I hook up the GE, I will see how much it pulls on startup too. SP are inefficient motors, and their speed is always less than that of a capacitor start motor. I feel the replacement capacitor start motor should work better as its speed will be much more consistent around 3600rpm, and they handle load changes much better.

 

[panthera]

There's no question

that motor efficiency has improved over time. It is, however, worth noting that shaded pole motors do have a few advantages over some other designs which can, under certain circumstances, justify their use despite lower efficiency. 1) Stalling out doesn't burn them out.  2) Super simple: If it ain't there, it can't fail. 3) As long as they are lubed, they have an indefinite life expectancy. As to our Twenty-Eight Hundred, the original motor has now run daily since 1984 with neither shaft leak nor broken chopper (a genuine weakness). That's not bad when you consider she's on her third mainboard and calrod.

 

[combo52]

Amount Of Waste Heat From A GE SP DW Motor

Is going to be around 375-500 watts, when you find out the exact # let us know, I have worked on enough of these to know what I am talking about.

 

The great thing about these crappy energy hog motors was they were great at drying up all the water that leaked at the trip shaft seal and even the main pump seal, I have seen many GE DWs that had leaked for years and the leaks went unnoticed because all the hot air blowing around dried up the water, if only they had directed the hot air through the DW chamber they could have left out the heating element for the dry cycle.

 

[panthera]

Formula

For calculating Watts on an AC motor:

<em style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248);">P</em><sub style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-weight: normal; background-color: rgb(255, 255, 248);">(W)</sub>[COLOR=rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248)] = [/COLOR]<em style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248);">PF </em>[COLOR=rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248)]×[/COLOR]<em style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248);"> I</em><sub style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-weight: normal; background-color: rgb(255, 255, 248);">(A)</sub><em style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248);"> </em>[COLOR=rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248)]×[/COLOR]<em style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-size: 22.4px; font-weight: normal; line-height: 40.32px; background-color: rgb(255, 255, 248);"> V</em><sub style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-weight: normal; background-color: rgb(255, 255, 248);">(V)</sub>

<sub style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-weight: normal; background-color: rgb(255, 255, 248);">[COLOR=rgb(0, 0, 0); font-family: serif; font-size: 16px; font-weight: bold; background-color: rgb(255, 255, 255)]Somebody will have a better figure, but if I recollect properly, this motor has a power factor of about .85. So - If the motor draws 6A @120VAC, then we're looking at 612 watts.[/COLOR]</sub>

<sub style="box-sizing: border-box; color: rgb(34, 34, 34); font-family: "Times New Roman"; font-weight: normal; background-color: rgb(255, 255, 248);">[COLOR=rgb(0, 0, 0); font-family: serif; font-size: 16px; font-weight: bold; background-color: rgb(255, 255, 255)]Now, I don't wish to be pedantic, but 100% of the work done by that motor is, ultimately, going to be heat.[/COLOR]</sub>

John's in the ball park on this. hell, anybody who's seen the fans on these knows that.

And, I LIKE shaded pole motors.

Actually, the Twenty-Eight Hundreds have a better power factor correction that people might expect - look at the power supply for the brain on them. I'd not be surprised it things add up pretty close to 1 in the end.

 

 

[Chetlaham]

I agree with everything Panthera is saying, however if the exact PF is known through a killowatt meter when the motor is pumping water, it is then possible to know how much heat is left in total.

 

[panthera]

Chet,

That would be a real world way. Anyway we cut it, these motors are horribly inefficient. And loud (blower). Still, over thirty years of constant service (I do re-oil the felt pad as per GE instructions every year or so) suggests they did get something right.

Would I replace it with the capacitor split-phase induction design if it were to fail?

Yes. Until then, it works well and makes a happy sound.

 

[Chetlaham]

Efficency

No, trust me, I agree with all you guys. A shaded pole motor (even in the 70s and 80s) was RARELY used in anything larger than a box fan due to the weight and inefficiency. I could be wrong in that some furnaces might have been SP, but thats it that I know of. No one in there right mind would make a 1/6 shaded pole motor, but I guess GE did. Part of me is saying it might have been marketing (think vacuum cleaners) where 5.5 amps looked better than 2 amps, but ultimately those decisions remain as secrets buried deep in GE's past.

Question. For you guys who know GE DW, any idea how much power the impeller itself uses to pump water? Im guess is at 100-150 watts, but be wrong in that regard.

As for myself I like the PSC a LOT more than the shaded poles. Quieter and no wind blowing about lol. Plus the new pump bodies make rinsing a heck of a lot better.

 

[panthera]

Suitability

One of the great things about the tremendous advances in metallurgy, manufacturing and electronics is the range of choice we have, today.

Back in the 1970's, an electronically controlled motor - Philips had them in their washers, for instance - was a rarity.

Today, we expect 'digital' motors to run at 100,000rpm + without the slightest hick-up.  There are reasons we still use them, though:

As long as they're lubricated, they have the longest life expectancy of any electric motor).

Run in very very cold and very very hot environments, as well in environments in which enormous temperature variations over a short period of time are normal.

Always start in the same direction (I'm not including the switched wire loop versions in this).

Self-starting.

Can be built as synchronous motors (I'm not getting into that discussion again).

Many can be speed controlled by super-simple electronic circuits.

Don't burn-up when stalled.

As close to silent, when properly built, as a motor can get.

Easy to magnetically shield.

Super easy to use the stator windings as a transformer.

Cheap, cheaper, cheapest to build.

 

Disadvantages - power PF without correction. Poor (that's an understatement) starting torque, lower efficiency than many other designs.

Shaded pole motors were and are an answer for applications in which certain needs take priority. 

Inexpensive to build.

Reliable - if it ain't there, it can't break down. Capacitors do have a limited lifespan and aren't tolerant of the high heat these motors can put away without difficulty.

Eventually, no doubt, we'll see more efficient motors, but for the moment they still fulfill a market niche.

Whether GE really needed to use them for dishwashers is a question I think we'll all have forever. 

 

[Chetlaham]

Agree with all the above. Everything has its plus and minus and thus its own niche.

I can't speak for GE's choices, but one thing is for certain: GE not only managed to put millions of descent dishwashers in homes all over the world, but inspired countless children to become future engineers and appliance collectors.

One of the earliest memories was playing around with a pot-scrubber and latter taking apart a GSD500D. Good times lol But no doubt it was GE that started my interests in appliances and consumer electronics. It was always fun to toy around with their products.

 

[combo52]

GE DW SP Motors

GE used these motors for one reason and one reason only, They Were The CHEAPEST  Motor To Build That Could Do The Job.

 

Every other DW manufacturer used a better MORE durable motor in their DWs including companies like D&M.

 

You are correct that these motors are simple, but simple does not mean they are necessarily more durable, because they run so hot and had cheap sleeve bearings and were poorly balanced I have no dough that most newer designs will outlast these SPMs. You are correct that adding a capacitor adds one more thing that can fail, but when you consider that modern capacitors on appliance motors have a life span of at least 50 years it really does not matter, LOL. I think I have seen one bad capacitor on a new style GE DW motor in the last twenty years.

 

Yes I agree Chet, that GE did introduce a lot of American homes to the work saving convenience of a built-in DW buy building them so cheaply and getting new home builders to put them in homes. A local development near here where Kettler Brothers built 1800 homes from 1963-1969 all had GE kitchens and they all had a GE BIDW. One of the men that worked for the builder said that GE sold them the DWs for $59 each.

 

The other great thing about GE selling all these cheap DWs to builders was the replacement market after they rusted out and the motors and pumps failed after 5-15 years, by that time most consumers were hooked and went out and bought a good DW, the reps at WP, KA and Maytag loved GE for this, and GE even put Waste-King on the DW map because of the way GEs rusted out people were looking for something that would not rust, LOL.

 

[johnb300m]

LOL HOLY MOSES
Ok John we get it.
You HAAAATE this motor!

 

[combo52]

GE DW SPMs

Hi John, it has nothing to do with hate and I though my post was pretty positive, using these cheap to build motors did allow GE to sell lots of consumers on having DWs, but there is not one redeeming quality of the SPM compared to the newer ball-bearing PSC motor for use on GE DWs, except the ability to evaporate water under the DW from leaks from GEs crappy leaky trip shaft seals.

 

In the nearly 20 years the newer PSC motors have been used in GE DWs our firm has seen one bad capacitor and one motor with a slightly noisy bearing, when I compare that with literately hundreds of SPMs on GE DWs that had loose fans, bad bearings, and open motor winding's I simply cannot say these SPMs were more durable.

 

[brucelucenta]

I remember that my folks had a GE 1200 dishwasher in their house from the early 80's till I bought them a new Bosch in the late 90's. The GE still worked reasonably well and I gave it to someone who used it longer. I personally have just never thought GE dishwashers were all that terrific. The ones I have used didn't clean all that well or really scrub the pots and pans well and sometimes left little particles inside and on top of the glasses. I had much better luck with Maytag built dishwashers than most other ones including Kitchenaid. Just never thought much of GE dishwashers or washers and dryers. Adequate at best and cheap, since builder models of GE appliances seemed to be in most homes built from the 50's on. I have always considered them to be basic machines, if you could afford nothing better.

 

[Chetlaham]

Better MORE durable motor

Well, if I may... I think this might be a bad taste from the early 90s up to the 2000s still lingering. In the 80s when GE's DW division peaked in every way possible, the shaded pole motors did not fail more than any other DW motor, in fact Id argue the least outside of KA. I have seen hundreds, if not thousands of mid 80s pot-scrubbers chucked out with the motors running and looking like they are mint. Also, the leaks you bring up were very, very common to the mids 90s-2000s GEs (hundreds had to be scrapped after only 8 years of use where I live, and most of that era always have crusty drain solenoid brackets), but rare on the 80s versions.

It was not so much the design, but run away cheapening and crap CC in the 90s that gave GE so many bad raps.