Live Steam Mad 17 Posted March 23, 2014 Hi, I recently got a CS Electronic brand PowerCheck Motor Dyno from Ebay (it's for Brushed motors ONLY) these used to cost like 500 Euros, I got it for 6 GBP, it was distributed by Schumacher back in the early/mid 2000's I believe. I made up some cables today for it and was able to test my Tamiya Super Stock RZ motor and get some figures and a graph out of it (see pics below for figures and graph) via it's PC connection. The user manual for the PowerCheck unit seems to say that the Power figure is the Mechanical Output Power (Mechanical Work Done) which seems to be backed up from what it says here where they water dipped and then motor sprayed and then added comm drops to a 20T stock motor here ;- http://forum.racing-cars.com/forum_posts.asp?TID=388 Have a look at the pictures I took (and performance graphs) if anyone's interested ;- https://picasaweb.google.com/101932667412801910198/CSElectronicPowerCheckMotorDynoForBRUSHEDMOTORSONLY The Geek in me thinks this is absolutely fascinating. I would love to be able to get a similar unit but for brushless motors and test out my 380 core sized, 540 can sized Keda C40 (Hobbywing clone) 13T 3300KV motor. But no doubt the cost would be horrendous for such a brushless dyno...I'll be testing more of the same motors, then a Dynatech, then a couple of Technigolds (real ones not the modern MFT RX-15 plus which seems to have different spec's to the original Technigold) then some stock RS540S motors etc. and maybe my Kyosho NIB LeMans 240S motor. Oh yeah, forgot to mention, there's 2 things that I don't understand about the graphs produced ;- 1) What is the significance of the green horizontal power line (103 Watts, it's not even the RMS of the peak power or anything?) ?! 2) How come the voltage (blue line) goes up to like over 9V ? The input was only 7.8V (I tested it on a multimeter before the test started, just the battery not even connected to the unit!). The back EMF can only be less than the input so it can't even be that? Wierd. Because of this, the figures for the efficiency and power seem to be somewhat inaccurate since e.g. on that graph, at max. efficiency of 76.1 per cent, if mechanical output is 115W then the power consumption would be 115 * 100/76.1 = 151.1W, therefore because current draw is shown as 18.4A, the input voltage was 8.21V (1.37V per cell), but I measured the pack voltage at 7.8V with nothing connected except the multimeter, before the test started. The PowerCheck seems to measure the voltage wrong and because of this some of the other figures would appear to be out as well? Can someone explain this? BTW I tried to test the motor with my Storm brand LiFe / LiFePo4 / Lithium Ferrite 2200mAh 6.6V battery but the Dyno kept saying "NiCad not charged" (it didn't like the low voltage compared to 7.2V 6 cells NiCd). Cheers,Alistair G. Share this post Link to post Share on other sites
