Lestronic Charger Question

[JohnnieB]

If your line voltage is dropping, I suspect the line voltage at the business next door is also.
Have a chit-chat with the management of the business next door. Commercial customer seem to have more influence than private citizens.

Tell them that when the line voltage is low, they may be paying more for the electricity they use and their electric motors are running hotter on lower line voltage.

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Or lodge a complaint with the Public service Commission (or whatever the agency that controls power companies in Florida is called)

[simple man]

Originally Posted by JohnnieB

If your line voltage is dropping, I suspect the line voltage at the business next door is also.
Have a chit-chat with the management of the business next door. Commercial customer seem to have more influence than private citizens.

Tell them that when the line voltage is low, they may be paying more for the electricity they use and their electric motors are running hotter on lower line voltage.

--------
Or lodge a complaint with the Public service Commission (or whatever the agency that controls power companies in Florida is called)

Good idea, John! I'll talk to him tomorrow. It's an auto repair shop and I know when their air compressor comes on!

[simple man]

I thought I'd update a little on the capacitors. I ordered both the 3µF and the 6µF today from "tedss.com"
In the meantime, I was digging through a box of caps I saved and found a 1µF 1,200V cap from an old microwave. For ha ha's I tried it in the Accu Power (has the 3µF cap). It came on, showed 12amps on it's meter, ran quietly and cool for 2½hrs, and shut off at 42.9V. The cart had been charged the day before and not used. I'm happy! I now know it will probably work fine when I get the right cap in it! I'm also pretty sure my Lestronic II will also do well once it gets it's new cap! I still haven't added the diode yet. I'll do that just to test before putting in the new cap.

[JohnnieB]

Originally Posted by simple man

Good idea, John! I'll talk to him tomorrow. It's an auto repair shop and I know when their air compressor comes on!

Must be a mighty big motor on that air compressor, or the transformer y'all share is woefully undersized.

At 240VAC a 10HP motor draws about 31A while running, but runs slower at 190VAV (95 x 2 = 190) while the mechanical load (Compressing air) stays the same, so more amps are drawn through the motor causing it to run hotter and because it runs slower it takes longer to compress than same volume of air, so it runs longer and costs more to run due to the motor's efficiency and its PF (Power Factor).

His air compressor may have a larger or smaller motor, but the effect is the same.

[JohnnieB]

Originally Posted by simple man

I thought I'd update a little on the capacitors. I ordered both the 3µF and the 6µF today from "tedss.com"
In the meantime, I was digging through a box of caps I saved and found a 1µF 1,200V cap from an old microwave. For ha ha's I tried it in the Accu Power (has the 3µF cap). It came on, showed 12amps on it's meter, ran quietly and cool for 2½hrs, and shut off at 42.9V. The cart had been charged the day before and not used. I'm happy! I now know it will probably work fine when I get the right cap in it! I'm also pretty sure my Lestronic II will also do well once it gets it's new cap! I still haven't added the diode yet. I'll do that just to test before putting in the new cap.

Looks like you are getting up to speed using the Alt key.
Here's a complete list of ASCII codes: http://www.theasciicode.com.ar/

If possible, measure the VAC output of the transformer with the 1µF, 3µF and 6µF installed.
I'm pretty sure the voltage will be higher with the higher capacitance values, but was wondering how much.
Apparently, the capacitance value also determines the max Amps out.

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The shut-off voltage is determined by the control board, so I doubt changing the capacitor will change it any.

[yurtle]

Originally Posted by JohnnieB

If your line voltage is dropping, I suspect the line voltage at the business next door is also.
Have a chit-chat with the management of the business next door. Commercial customer seem to have more influence than private citizens.


Or lodge a complaint with the Public service Commission (or whatever the agency that controls power companies in Florida is called)

PSC controls non-governmental power companies, but at least here in Georgia, if you get power from a local government, your only option is to complain to elected officials. My last house and current house are both served by cities. I lived outside the city limits in both houses, so Mayors and city council members weren't worried about me trying to vote them out of office.

[simple man]

An update on the capacitor discussion: I finally got my capacitors in and "JohnnieB" asked me to do a simple test. I am using the Lestronic II charger (model 07850), and starting with no capacitor, up to the 6µf which it takes, I'm taking voltage readings on the secondary transformer windings disconnected from the diode pack. Here are the results:
First I measured the AC line voltage (121.2). I then made sure it was reasonably the same for each step of the tests. The test consists of measuring the secondary voltage starting with no capacitor, then a 1µf, 3µf, and finally the correct 6µf.
No capacitor --- 61.7VAC transformer very quiet
1µf cap --- 129.5VAC transformer loud hum
3µf cap --- 85VAC transformer quiet (mild hum)
6µf cap --- 89.5VAC transformer quiet (mild hum)
This tells me that the rating of the capacitor definitely influences the secondary voltage output. I'm going to measure the DC charging voltage when I get the charger back together and connected to the cart. I'll post that up tomorrow. I'm learning a lot working on these!

[JohnnieB]

Thanks for the info.

The really high voltage with the 1µF is a surprise.

The un-boosted (no-cap) is a little above nominal (60VAC) and the boosted output is a little below nominal (90VAC), so that transformer might need a little more capacitance.

I'm not too sure you'll see much difference in DC output voltage since that is pretty much regulated by the battery it is connected to, but there ought to be a difference in output amps.

Technically, the output is a classic a half-wave rectifier circuit, so the DC voltage will be 1/2 the secondary AC voltage due to the transformer secondary being center tapped. So the DC volts when unloaded will be 45V if the AC voltage across the whole secondary is 90VAC. It might read a bit higher than that because the peak voltage of 90VAC is 127.26V (90 X 1.414) and some DC voltmeters get confused by the ripple.

The amp flow is determined by the difference in voltage between the rectified secondary voltage and the battery voltage. Of course, when the secondary and battery are connected together, they are at the same voltage. What happens is that the secondary voltage decreases as amp flow increases, so the the number of amps flowing will be whatever it takes to drag the secondary down to the battery voltage, which to some extent will be increasing as amp flow increases.

Problem is, if the difference between to secondary voltage and the battery voltage is too great, the resulting amp flow could damage the battery. Basically, if you use too small of a transformer, it takes forever to charge the battery and if you use too big of a transformer, you can ruin the battery. That is where the Ferroresonant Transformer design comes into play. It "Magically" limits the maximum number of amps to a safe level.

[simple man]

I was surprised at the high voltage created by the 1µf cap too. I double checked it twice so I know I read it correctly! The loud hum was also surprising to me as well. I only left the charger connected this way for a few seconds so I wouldn't damage it. I just looked at the 1µf cap and it says "internal resistor" on its nomenclature. Possibly this affected the reading I got when testing it in the circuit. It worked quietly in the Accu - Power charger (model 13800) and produced a charging current, although low (13amps at start). I realize that even though these are both made by Lester, they have vastly different transformers! I'm out to the shop to put the Lestronic II back together, charge my cart, and I'll report the findings on the charging current at startup and the final phase voltage!

[simple man]

To update from yesterday: I assembled the Lestronic II and connected it to the AC line and then to the cart. It started at 22amps, ran for 2½hrs, and leveled out at 45.3V and 3amps before turning off. The cart was charged the previous day and not driven. I'm happy!!! My friend's happy. His Accu - Power charger works properly now too!
Now, on to figure out how to test a capacitor for capacity. I now have a weak one to play with! (6µf)