I have a strange issue with the PSU of an elliptical.
The factory supplied unit is a linear wall wart type. Rated on the case at 6V 1000mA.
It accidentally got crushed between the wall and a piece of furniture so I decided to save the trafo for a future project and buy a new PSU from Amazon. SMPS rated at 6V 1A. Plugged it into the elliptical and the display turned on but very dim. When I try to adjust the tension on the flywheel, it barely increases from minimum.
I figured it's not meeting spec and returned it. Next I bought another SMPS, this time rated at 6V and 2A. Plugged it in and same issues. Measured it and it's doing 6.2V so it's not faulty.
Why would a linear PSU work but two different SMPSs with the same (or higher) rating not work? I'm baffled.
The factory supplied unit is a linear wall wart type. Rated on the case at 6V 1000mA.
It accidentally got crushed between the wall and a piece of furniture so I decided to save the trafo for a future project and buy a new PSU from Amazon. SMPS rated at 6V 1A. Plugged it into the elliptical and the display turned on but very dim. When I try to adjust the tension on the flywheel, it barely increases from minimum.
I figured it's not meeting spec and returned it. Next I bought another SMPS, this time rated at 6V and 2A. Plugged it in and same issues. Measured it and it's doing 6.2V so it's not faulty.
Why would a linear PSU work but two different SMPSs with the same (or higher) rating not work? I'm baffled.
Is the original power supply 6 V AC and you provided 6 V DC? Sometimes manufacturers use voltage doublers and other tricks to create a split/bipolar supply from a single AC source. That won't work with a DC source.
It'll be difficult to find a wall wart that has a mains transformer in it, so if your equipment needs 6 V AC your best bet is to find a small transformer and put it in a box.
Tom
It'll be difficult to find a wall wart that has a mains transformer in it, so if your equipment needs 6 V AC your best bet is to find a small transformer and put it in a box.
Tom
Sometimes they are AC output. Do you remember seeing diodes / cap when you saved the tranny part? (tomchr beat me to the same)
Maybe the elliptical was damaged by the original accident?
(But what is an "elliptical"? i only know it as a stretched circle as in geometry)
(But what is an "elliptical"? i only know it as a stretched circle as in geometry)
Definitely DC. It's both spec'd on the case and it's made up of a trafo, 4 rectifier diodes and a cap.
The elliptical (an exercise machine between a treadmill and a bike) was working just fine. I unplugged the original psu from it, then I pulled out the furniture that was against the wall wart and it disintegrated once the pressure was taken off it. In other words, the original psu did not damage the machine.
I'll likely take the parts from the original unit and make a new case for it but I'd still like to understand what the issue is.
The elliptical (an exercise machine between a treadmill and a bike) was working just fine. I unplugged the original psu from it, then I pulled out the furniture that was against the wall wart and it disintegrated once the pressure was taken off it. In other words, the original psu did not damage the machine.
I'll likely take the parts from the original unit and make a new case for it but I'd still like to understand what the issue is.
Open the exercise machine and see what is inside.
And use a linear PSU, sometimes the cheap SMPS are not pure sine wave, or add caps across those SMPS and see what happens.
And use a linear PSU, sometimes the cheap SMPS are not pure sine wave, or add caps across those SMPS and see what happens.
You may want to connect the original parts to see if it still works with the remains of the original supply. Baffling I understand with the dim lit LED display and all.
Dim display, disconnect the motor, then check voltage to display.
If it gets brighter, the motor side has an issue.
Don't you think a 12V or 24V motor would have been a better choice?
See the motor ratings on its label as well.
6V 1A is only 6 Watts, not much.
If it gets brighter, the motor side has an issue.
Don't you think a 12V or 24V motor would have been a better choice?
See the motor ratings on its label as well.
6V 1A is only 6 Watts, not much.
I haven't taken the machine apart but I don't think there's a motor in it. I think it works with a brake on a flywheel. More brake applied = higher resistance. The brake may be mechanical like car brakes or I suppose it could be magnetic.
Either that or the circuit relies on the voltage of the power supply being higher than nominal at light load. The original supply had no voltage regulation after all.