Have you ever wondered how much power it takes to get your Loco moving or how many amps it's drawing? You can always break out the bulky old meter, But wouldn't it be nice to have a meter right there on your controller? Well here is my solution. I picked up a 0.000-3.000A /0.00-33.0V dual Led digital gauge meter off eBay for $7.00. Broke out the trusty old dermal and did a little soldering. I'm still testing it but so far the controller and built in circuit breaker are working great as is the new built in meter.
David, Every once in a while I see something and I physically smack my head and say "Why didn't I think of that?!?!" This is one of those times. Brilliant. Simple, useful, inexpensive. Well done. -Rob(A) AZL
I've had several request asking what meter I used and how to wired it in So Here you go. The meter I used is a Digital DC Volt Amp Meter 0-33.00V/0-3.000A made by DROK You can find them on Amazon here http://www.amazon.com/gp/product/B00IZTTAKO/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 or you can find a cheaper version on eBay Just do a search for " 0-33V 3A DC Voltmeter Ammeter Digital LED Amp Volt Gauge meter" Shop around prices very. Installing a volt/amp meter in the Rokuhan RC-01. Step 1: First remove the battery and unplug any plugs or cords you have hooked to it. Now turn your RC-01 controller over place it face down with the connecting plugs on the back of the unit facing away from you. And removethe 4 Philips screws located in the center of the raised foot in each corner. Carefully lift the bottom straight upabout one inch and rotate it back sit it down behind the front half, the wires connecting the two half’s are not very long so be careful not to pull them apart. Remove the battery compartment lock pin & spring and set them aside along with the screws from the bottom. Step 2: Now take a few pictures of the inside so you will have a reference to help put things back together. Step 3: Unsolder the red and black wires from the bottom half andset it aside Step 4: Remove the accessory plug by gently prying it out of the housing, trace the wires back to the circuit board, Unsolder and remove them or cut the wires and tape the ends so they can't contact each other or any thing else. Step 5: Carefully layout the area for the meter and cut it out. It should fit flat against the housing that holds the power plug on one side andyou will need to notch the corner of the "point #2" plug housing on the other side for a 45.5mm wide hole. Now for top to bottom I laid mine outusing the top of the Accessory lettering as the top edge and measuring 26.5mm down from there to get the bottom edge. There is no room for error here so measure twice before you cut. I used a Dermal with a cutoff wheel to cut a little inside the lines then trimmed it out the rest of the way with a razor knife and a small hand file. Once you have the housing cut out make sure you have the meter turned right side up and snap it into place.
Step 6: Next is probably the most difficult part. You will need to cut one of the electrical traces on the circuit board. Locate the 8 pins from the direction switch and the 2 pins from the orange colored diode on the back of the circuit board. (Circled inpurple in pic 3) Now you will need to cut the trace between the 2 center pins from the direction switch and the orange diode. (The area circled in Red in pic’s 4 & 5.) I used a cutoff wheel on my dermal to cut/grind away the trace connecting the two. Step 7: Solder the thick black wire from the 2 pin connector on themeter to the end of the orange diode (marked with a black circle in pic 4) Solder the thick red wire from the 2 pin connector on the meterto the 2 pins from the direction switch next to the orange diode (marked with anorange circle in pic 4) Solder the skinny yellow wire from the 3 pin connector onthe meter to the 2 center pins on the other side of the direction switch (marked in yellow in pic 4) Solder the skinny red wire from the 3 pin connector on the meter to the center terminal on the power switch. (marked with a blue circle in pic 6) The thick wires from the 2 pin connector on my meter were too short so I tossed the connector and soldered in some new wire sections. Note the orange wire in pic’s 5 & 6 (I didn’t have any red wire on hand so I used what I had “Orange”) Tape off or remove the thin black wire from the 3 pin connector on the meter. (It’s not going to be used)
Step 8: Re connect (Solder) the red and black wires back onto their respective terminals on the bottom half. (The ones you removed in step 3) Step 9: Set the spring back into position on the top half then the battery lock pin on top of it, (the long side goes into the spring) and carefully close the controller back up. Replace the screws and snug them up. Careful don’t over tighten them. Step 10: Clean your track Put the batteries in or plug in the power adaptor, hock it to your track and give it a try.
Shamoo, David's modifications instructions ought to be added to the modifications sticky thread! Mark
Well I hit a brick wall trying to find one of these meters, the one from Amazon turned out to be a temperature readout, Amazon refunded my money, then I ordered one from Hong Kong and after 3 weeks they refunded my money and said not more stock, only good thing was with drop in Canadian dollar I made 10 percent on my money in three weeks. so I keep looking this was so neat an idea everything I have been able to find so far is for much higher amps and has a larger sampling bridge so no good for this application, but would work in a car etc.
I was able to buy two of the meters from E-bay with green and red LED's. Took two weeks to arrive but they don't work as advertised. While they are listed for 0-33V, mine don't read until 9V. The ammeter range was 0-3A and 0.5A is as low as I can get them to go. I have corresponded with the seller and they say they will send replacements. We'll see if the new ones work any better. If not, I hope the E-bay protection works.
Garth, Woodworker19 Sorry to hear that you are having trouble finding /getting a meter that works. Try this one it's the same make and model as the first one I got off eBay. http://www.amazon.com/gp/product/B00IZTTAKO/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 David
Beyond a doubt, David found a perfect unit for the throttle. But it isn't too difficult to make appropriate meters with just a couple of resistors. Virtually all digital meters are 0-200mV DC units. If you connect a 1 ohm 1% resistor across the inputs of a 200mV unit, you get a 200mA unit. If you build a 100:1 resistor divider (two resistors) across the throttle output and connect the meter across the smaller value resistor, to turn that 200mV meter into a 20V meter. These techniques are basically what the meter manufacturers do. Mark
I haven't given up hope yet. I do have two meters in hand that work if I can come up with a 12V project. Hopefully I won't end up with four !
Add one more conversion to the roster! My only regret: when I went to cut the case I could not find my dremmel. I got impatient and used a cordless drill with a 1/4" bit. Not exactly clean cuts, but it works great!
I am curious does the motor really consume only 15ma and run? It looks like too little, did you folks get a chance to cross check with a DMM. Just the display on the meter will be consuming more than that.
The ones I've seen (http://www.mpja.com/Digital-Panel-Meters/products/52/) and have Chinese spec sheets for don't read below a few volts. Make sure you read the instructions. Some are 'self powered' meaning a minimum input voltage is needed, like 3 to 4 volts. Some that take a power supply often say it has to be isolated ('floating') meaning you can't tap the Rokuhan's internal rectifier/cap as a supply. If you can wait a week or two, I get most of my stuff direct from China thru Aliexpress (Alibaba wholesale's single unit market place, like an Amazon). http://www.aliexpress.com/wholesale...=SB_20150202205239&SearchText=led+panel+meter Mark, true. But a analog meter just won't fit in that box.
