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Lohja
07-22-2003, 12:23 AM
On Sunday 20 July 2003 I depleted my HT batteries (per the HT’s charge indicator) to one full bar and one blinking bar. While recharging the HT to full charge I attached a wattmeter, a voltmeter, an ampere meter, a duty cycle meter, a power factor meter and a digital clock (actually, they are all included into one meter housing). The following data was collected. Notice that until
0.59 hr (35.4 minutes) into the charge there was actually no battery recharging taking place. However, at 7.3 watts there was probably some “trickle” charging.

Time..Watts..PF..Duty-Cycle..Amps..Volts

3 min..... 7.4.....NR.....5.....NR.....119
12 min..... 7.3.....NR..... 1..... NR.....119
0.29 hr.....7.4.....NR.....0..... NR..... 119
0.47 hr.....7.3.....NR.....0.....NR.....118
0.58 hr---I noticed major changes taking place in ampere readings.
0.59 hr.....55.6.....1.....0.....0.33.....118
1.21 hr.....104.8.....1.....18.....0.85.....117
1.47 hr.....106.9.....1.....37.....0.87.....118
2.32 hr.....108.5.....1.....56.....0.88.....117
3.26 hr.....109.7.....1......67.....0.88.....118
4.01 hr.....110.2.....1.....72.....0.9.....117
7.19 hr.....7.3.....NR.....46.....NR.....120

Total watt-hours recorded as being used during this charge = 424.
Total cost to charge at 10-cents/kwh = 4.24-cents (will vary with local rate/kwh).

Notes:
1. NR = No reading indicated on meter.
2. Duty Cycle = the percent of total charging time the wattage input was more than 100-watts (the threshold I chose).
3. PF = Power Factor.

During the first 35-minutes of the charge, the wattmeter was very erratic. It peaked (instantaniously) at 186 watts when the 120 vac was first plugged into the HT. For the 1st 35-minutes the wattage varied all over the map up to 70+ instantaneous watts; but the predominate number was 7.3 watts. So, that’s what I recorded. The peak amperes were 2.3 again at the initial plug-in and had no other reading until the 0.47 hr when it flickered between 0 and 0.4. I continued to record it at zero during this period as the higher numbers were instantaneous and not constant readings. At a PF = 1, the wattage should equal the amps times the volts. It’s close but not exact. Why? I do not know!

The bottom line is it appears there will be no helpful charging of the HT batteries until it has been plugged in for at least
30-minutes. So forget the quick charge at Starbucks. It appears the HT is preparing its batteries for charging during this initial 35-minute period. Then, after this initial preparation, the charging gets serious. Based on the duty cycle readings, I’d estimate my full charge took approximately 5.5-hours.

Only one test--- but it’s a start.











Visit my Segway Blog page at http://galsegway01.blogspot.com




clm
07-22-2003, 12:44 AM
Great data!

Thank you - very useful for everybody

Chris

TedS
07-22-2003, 12:53 AM
That information is good to know. Thanks for taking the time to record it and share.

It looks like there may be no topping off the batteries in a time less than 30-35 minutes. However, charging from a one-bar down condition may be different.

Ted

Balance
07-22-2003, 02:42 AM
Were the batteries cool when the charging cycle started or could it be possible that the first ~30 minutes were the charger circuit waiting for the batteries to cool down?

-Adam

KonaSegway
07-22-2003, 03:56 AM
Hi Lohja,
I used the kilowatt meter that pt suggested and I got some different results. I rode the seg til it was completely dead .. it only took 10 minutes after plugging it in before the full charging started, so stopping for a quick charge may work depending on how low the batteries are maybe ?

Here's some (un)scientific data : http://www.konasegway.com/kilowatt.shtml

Aloha,
Sam


http://www.konasegway.com

toybuilder
07-22-2003, 07:47 AM
The manual says that the Segway will spend some time to "ready the battery" -- if it is too hot OR too cold, it needs some time before going into the regular charging cycle. If you look at the charge indicator lights, you'll know when it switches from the "preconditioning" stage to the regular charging stage.

http://www.pasadenasegway.org/
A bicycle in 1897 cost $25 ($2,200 today adjusted for inflation).
A Ford Model-T cost $850 in 1908 ($75,000 today adjusted for inflation).
(Can anyone point me to historical prices of horses?)

GlideMaster
07-22-2003, 11:41 AM
<center>Great info Lohja, it's good to keep some of this info in mind.</center>

<center>The GlideMaster</center>

edh
07-22-2003, 12:08 PM
On this topic - If I plug in after riding (still a little warm to the touch), it sits in blink mode for a long time, sometimes over an hour. I have even tried unplugging it for a few minutes, as the manual suggests, and plug back, it still takes a while at times - 20-40 mins to get solid green lights.

Does anyone else see this on theirs or do I need to call LLC?

Thanks,
-Ed

opti6600
07-22-2003, 12:32 PM
Ed, I have a feeling it has to do with the amount of current the batteries can take while they're hot. The 20-40 minutes is just time to cool down, probably, and also the battery should be at room temperature to accurately test the state of the pack (as the slow blink usually denotes - testing or topping charge).

---------
Let's just take the safety labels off of everything and let America's problem sort itself out.

Lohja
07-22-2003, 01:04 PM
I have some new data which is more encouraging. The initial data was with "cool" batteries. They had at least one-hour rest; but the temp was in the 90s. This morning, after 18-hours rest, I recharged my batteries with the top bar blinking and the air temperature at about 80F. Here is my data:

Time......Watts......PF......Duty-Cyc......Amps......Volts

2.1 min.....7.6......NR........0............NR........ 119
Note: At plug-in the watts spiked at 192.3 and the Amps spiked at 2.05.
The watts were doing their "start-up dance" as described in post #1.

3.3 min.....105.2....1........40............0.86...... 118
8.53 min....106.2....1........67............0.87......1 17
12.0 min....106.7....1........76............0.86......1 18
15 min......108.5....1........89............0.88..... .118
Stopped recording beyond this 15-minute point as I was interested in only the initial readings.

So, with my very limited data (based on only two tests) I can come to the following observations:

1. Charging starts quicker with the most battery power remaining. If you are going to plug-in while gliding, the sooner you plug in--the quicker the charge will begin. Don't wait until you are almost depleted as it could take up to 30-minutes to actually begin charging.

2. Charging watts are between 105 watts and 110 watts. Having less battery doesn't mean it will charge at a quicker rate. After the initial "battery dance" the charging rate is the same whether you are near a full or near empty battery capacity.

3. Charging current is about 0.9 amps max.

4. Cost of charging is only a few cents per a full charge (about 0.5 Kwh for a full charge) At 4-cents/Kwh, it would be 2-cents for a full charge.

5. A full charge will take less than 6-hours.

Based on my glide at the beach yesterday, my HT doesn't do well in deep (about 6-inches) sand. I spun my wheels backing up and had a "shut-down". In smooth sand, it worked fine.

Visit my Segway Blog page at http://galsegway01.blogspot.com

Deviant
07-23-2003, 11:13 AM
Fantastic information. Thanks for sharing!

ElectraGlide
07-23-2003, 12:15 PM
Thanks for sharing all your data with us. It is indeed helpful to understand what happens during our charging cycles to best utilize our machines.

Steve