anyone tried to using Jebo WP40?

[degibson84]

i love the time difference mine left for its destination tomorrow


The item (LK022490898HK) left Hong Kong for its destination on 27-Mar-2013

 

[degibson84]

no outside links please we dont want them to shut this thread down .. i think this is the hottest topic on RC right now ..

it is probably the hottest topic on every forum i see this thread linked everywhere

 

[rrasco]

Well i know i'm Portuguese and maybe my english its not good enough but few pages back i posted that i did it with a arduino!!!
There is a video showing it and i can send the code...

Should you invent the wheel when someone already did it?
I wouldnt but thats up to you...
Arduino and components should cost around 30usd... But hey... Why should you spend 30usd on a cheap diy instead of 200 or 300 bucks buying other stuff probably its why people go over MP40 instead of WP40...

All the best.

If it's the one I am thinking of, I saw it, but you didn't include details on how you actually did it, did you? Schematics and a bill of materials? I'm very familiar with arduino and the atmega328. I'm all about DIY.

 

[SimonSKL]

If it's the one I am thinking of, I saw it, but you didn't include details on how you actually did it, did you? Schematics and a bill of materials? I'm very familiar with arduino and the atmega328. I'm all about DIY.

rrasco, I will be very interested in your build using arduino and custom codes to run this pump. Please provide as much detail, material and parts list, and schematics as possible to us novices. Thanks!

 

[jtomasi]

It is advisable to use PWM to control the pump. It is designed to run at 24v and only 24 volts. You can reduce the voltage to reduce the speed, however it will increase heat and is not the right way to control a DC motor. PWM pulses 24 volts which therefore controls the speed of the motor. The cable from RA will correctly do this via the built in box when hooked to a RA or Apex.

is this true? Has anyone experienced abnormal or increased heat by throttling the voltage? When I asked if the voltage adjuster and RA cable were the same, someone said they were - now we have contrasting answers. Anyone else have an opinion/facts? I don't want to catch my house on fire

 

[bluewater921]

it is probably the hottest topic on every forum i see this thread linked everywhere

your so right cause i have even seen links on face crank ..

 

[barry_keith]

no outside links please we dont want them to shut this thread down .. i think this is the hottest topic on RC right now ..

Yup, that's why I said send me, not post! ...

 

[88rxna]

It is advisable to use PWM to control the pump. It is designed to run at 24v and only 24 volts. You can reduce the voltage to reduce the speed, however it will increase heat and is not the right way to control a DC motor. PWM pulses 24 volts which therefore controls the speed of the motor. The cable from RA will correctly do this via the built in box when hooked to a RA or Apex.

what about us reefkeepers???

 

[andyrm66]

is this true? Has anyone experienced abnormal or increased heat by throttling the voltage? When I asked if the voltage adjuster and RA cable were the same, someone said they were - now we have contrasting answers. Anyone else have an opinion/facts? I don't want to catch my house on fire

Wont catch your house on fire. But I promise you the voltage adjuster and RA cable are different. I talked with Roberto, who did the cable for RA.

Look up some stuff on DC motor control.

 

[SimonSKL]

Wont catch your house on fire. But I promise you the voltage adjuster and RA cable are different. I talked with Roberto, who did the cable for RA.

Look up some stuff on DC motor control.

From what you know about DC motor control, if I don't have RA but want to slow down the pump, will the option of using a 24v PS with a PWM LED dimmer mentioned earlier a better choice to control the pump than a variable PS?

 

[andyrm66]

Yes, because the PWM is still supplying 24 volts, but pulses it, on-off-on-off and different rates which correlate to pump speed.

 

[andyrm66]

It changes the width of the pulse (sine or square wave) to control the motor speed.

 

[jtomasi]

Thank you for providing that information - I have the RA so I am all set, but people should be very appreciative that you chimed in with FACTS (seems like people answer questions without any backup info).

 

[hillscp]

You don't need to. Just measure the voltage on the output of the dimmer with a Multimeter.

Mark the dial where it is completely off. I marked mine on the dial at about 5 o'clock position where it says off.

Turn the dial slowly clockwise until you get 12V on the multimeter. Marke that position. Mine is about 9 o'clock.

Turn the dial all the way clockwise until it stops. That should be about 24V. Mine is about 2 o'clock.

As long as you keep your dial between the 9 o'clock and 2 o'clock positions, you have 12 to 24V to your controller and pump and you won't worry about your controller or driver not getting enough operating voltage.

I'm curious, if that PWM dimmer sends a chopped up continuous 24v then how does a multi meter measure 12v?

 

[jtomasi]

I dont think that dimmer is PWM, which would answer that. Pure speculation though as I just looked on the ebay site and didn't see anything about PWM

 

[andyrm66]

That ebay dimmer -white thing pictured, isn't a PWM dimmer. It is a rheostat. Just a variable resistor. It "shaves" off excess voltage in the form of heat. Thus, PWM is much more efficient means of control.

A digital volt meter will get you close, but depending of the pulse width and sampling rate of the meter you may encounter noise. A scope is what is really needed.

 

[hillscp]

Right, In his very next post simon mentioned it was PWM. I didn't bother to check. Now that I looked the answer is obvious

A lot of those "PWM" dimmers don't mention frequency or duty cycle. Hmmm

 

[dougdstecklein]

I guess I just wasted $6 on the white dimmer on ebay. Can someone pm me a link to the dimmer I need to get.

 

[rrasco]

I'm curious, if that PWM dimmer sends a chopped up continuous 24v then how does a multi meter measure 12v?

Because that is how PWM works. If it's 24v and it's measuring 12v, it's fairly safe to assume it's running around 50% duty cycle. As was mentioned, you would need an oscilloscope to see the wave of the signal.

PWM Fun Fact: Did you know that LEDs are dimmed by the frequency they pulse and not their brightness? LEDs pulse constantly, the brighter the LED, the faster it's pulsing.

EDIT: Okay, so I realized you were talking about the ebay rheostat. At any rate, PWM still works as I described above.

 

[SimonSKL]

I happened to have a "real" PWM controller that I bought from eBay to test the voltages again.

http://www.ebay.com/itm/130574312785?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

As you can see, a real PWM controller can change the voltage. I know the LED Dimmer didn't say it was PWM but I think it operates on PWM mode.