s646se or s636

[skswan]

I have two wheelchairs one is a tilite zra and my power chair is a pronto sure step m51. This chair has served its purpose and I have gotten alot of use out of it...but! It is soo uncomfortable, the seat is a van like seat. I use this chair inside (because of knee problems) and go outdoors quite oftento take the dog for a walk. The area I live in is hilly and the round trip I usually make is about 3-3.5 km. The chair does this with no problem but I would not want to try it twice without charging.

The tdx sp caught my eye when looking for a chair but I have changed my mind on it cause it seems to have quite a few problems. I am now looking at the s636 or the s 646se. I like the speed of the s646se because this would give my dog a better workout (trust me he has lots of energy to burn!). I wont be using this chair offroad, how well does everyone think the 646se will hold up for range (because of the speed I am a bit worried).

[Burgerman]

The hills are your problem, if it is a "fast" chair. They eat up power. I would be tempted to go with a slower chair with biggest batteries possible. Also depends on your weight.

Your chair only has 35Ah batteries, and is 4mph. So has about the same range as a faster powerchair with bigger 70Ah batteries. But you will still be limited to about the same as you are getting now, unless your batteries are ready for replacement?

[LROBBINS]

You might also think about adding an external Anderson connector (see Burgerman's battery pages) and a more powerful charger so that you can opportunity charge whenever you have a few minutes near a power source, or go whole hog and put in two Anderson connectors and a "shunt" plug for driving so that you can quick charge at 12V using either a good 12V charger or your car's alternator (again, see Burgerman's batter pages). John (Burgerman) has really put together the very best information and advice about lead-acid charging!

It does mean modifying the chair, just a little for the first case, a bit more for the second, but a few minutes of quick charge with a powerful charger can almost "refill" the batteries - just remember to also do an full, overnight, charge as well to keep the plates in good shape.

Ciao, Lenny

[skswan]

I am about 200 pounds. The chair I currently have had batteries replaced about a year ago. The 646se is supposed to be a 8.5 mph chair. If it will only get the range of my current one I think I will be going with the 636. Hopefully I can get one to try before I buy.

[Burgerman]

The batteries in your current chair may be giving you a worse impression of what should be happening though. For a couple of reasons.

1. Theres only really 2 battery types that should be used on a powerchair. They get a terribly hard life and are tortured.
a) MK Gel or Sonnenschein (same thing one copied the other).
b) Enersys Odyssey. Simply forget anything else as they will likely give worse performance, and worse lifespan.
Completely forget anything else, esp if cheaper!

2. Used in lab conditions, expect to get around a years heavy daily use to around 80 percent discharged. At the end of this time you WILL have lost about 20 to 30 percent of the range.

So a NEW set of QUALITY batteries may improve your current situation.