I have always been meaning to do this - thank you for providing the stimulus for me to do it!
I have just measured a 60W bulb for a 240V supply. At room temperature it was 80 ohms.
Now, if it consumes 60W when on, then 60W = 240 * 240 / R. The resistance when on is therefore ~960 ohms or 12...
Please upload the relevant parts of the circuit diagram so sensible suggestions can be made.
If it is a DC circuit then you are almost certainly overloading the contacts. DC does not quickly (within 10ms for 50Hz) extinguish any arc by going to zero as AC does, so much more damage is done to...
I am becoming concerned that you do not appear to have the basic knowledge to do this diagnosis or repair in a safe manner. Anyone with even slight knowledge of DC motors should not need to be told how to check brushes.
Working on battery powered wheelchairs is EXTREMELY DANGEROUS unless and...
See the youtube video links in post #6 where similar motors are disassembled and the brake removed.
I am certain you are correct.
With a little more thought I should have realized that there needs to be a way of moving a chair with a flat battery, and disengaging a worm is much more...
Yet another thought.
See this forum post One of my wheelchair motors overheats and stops working which links to this video Electric Wheelchair Motor Test & Brake Removal by VOG (VegOilGuy)
youtube has several videos - eg see
- inside a wheelchair motor (VLOG 333), and
- diagnose and repair...
And some more thoughts ...
1 The manual says there is a brake. It or something else is probably binding. Check what. Is greasing required?
2 It is always worth checking the brushes on a DC motor.
That sounds like the brake is sticking on. Freeing the brake may be enough to allow it to continue operating assuming the brake has not been damaged so much as to make it unreliable in future. The brake prevents a stationary chair from moving so you are at considerable risk when using the...
Curtis Instruments make a range of controllers including the 1223 model for my wife's heavy duty off road mobility scooter. The 1223/1233 range goes from 24 to 36V, with current limited from 45 to 110 Amps, and with a 1 hour rating of 30 to 40 Amps.
The output circuit is multiple power...
Earnshaw's theorem proves that it is impossible for a static system using only paramagnetic materials (such as ferromagnetic iron) to levitate stably against gravity.
Before going too far check with your local police to see if they will assist you to recover it as they may deem it not worth their efforts to recover a bicycle.
As you park your bike at home, fix a contactless charger to the wall, and a receiving coil on the bike so as to charge the battery whenever the bike is at home. You could have a tiny socket on the bike and plug it in - in time, it would become an automatic action you wouldn't forget.
A problem...
Thanks. That is the answer I was looking for - basically, there isn't much difference in charging efficiency between old and new batteries so my "miles per kWhr of mains electricity" won't change much as the battery ages.
I think Battery University says you should always power off your PC...
Battery University is interesting. It says "Charge efficiency is about 99 percent and the cell remains cool during charge" so, at least for a newer battery, the charge efficiency is excellent.
It also says
"EV makers must further account for capacity fade in a clever and non-alarming way to...
An electric car has, say, a 50 kWhr battery.
1. How much electricity, in kWhr, is needed to add 1 kWhr of stored electricity to the battery?
2. After several years, the battery capacity has, say, fallen to 25 kWhr. How much electricity, in kWhr, is now needed to add 1 kWhr of stored...
The point about an inductor is that it tries to keep the current flowing through it constant ... which means the current tries to flow through the now open switch contacts.
The voltage across the open contacts rises until the medium breaks down and allows the current to flow.
Years ago I used...