Well, I figured how to get artwork uploaded into the Design Space
...but, adjusting & workin' with it, is gonna take some more learnin'
Also, been thinkin' & workin' on the dash board a bit more
...& workin' on getting it wired up.
It'll just have an On/Off switch
...a Reverse switch
...a PZEM-051 power meter
PZEM-051 100A DC LCD Digital Panel Power Meter KWh Voltmeter Ammeter With Shunt | eBay
...& a small GPS speedometer
Car Digital GPS Speedometer Odometer Head Up Display Overspeed Warning Alarm HUD | eBay
The power meter can be/is "powered" by up to 100V (this vehicle has a 48V system/~54V top charge)
...but, the speedometer can only be powered by ~5V (like from a USB port)
So to "power " the speedo, I got the bright idea to build a voltage divider (to reduce the 48V (pack voltage) down to 5V)
I did some calculations & it looked like, if I used a 2,000 Ohm 2w resistor for (R1) & a 240 Ohm 2w resistor for (R2)
...the combination would reduce 48V down to ~5V
So, I assembled one then tested it with a MM
...& there was ~50V going in & 5V coming out
...but, when I connected the speedo it wouldn't/couldn't "power" it
So, I did some investigating, here are the specs
Specifications:
Model: C60S
Screen size: 3.0 inch
Product material: ABS+PC
Input voltage: DC 5V
Working temperature: -30~80°C
Input current: 50~120mA, can be powered by power banks (It has no built-in lithium battery and only saves the total mileage data when power is off, other data is not saved)
Satellite positioning speed: 1 to 3 minutes in open space; no satellite signal when indoor. (rainy days affect satellite positioning speed)
So, it looks like the input current is 50~120mA (.05A-.12A)
...& with the (2) 2W resistors that I used "in series" (I believe) the math would be (2W/48V = .04A)
Then, I tried using (2) of the 2,000 Ohm resistors & (2) of the 240 Ohm resistors (4W/48V = .08A)
...but, the speedo still wouldn't come on or "light up"
So then, I said, "what the
" & tried a (4) 2K Ohm & (4) 240 Ohm set up
...& Boom! it came on or "fired up"
But, I've noticed that the (4) 2K resistors warm up & get kinda hot
...even when NOT "in use" or "powering" the speedo (parasitic draw?)
I understand resistors sometimes "warm up" during use
...but, how warm or hot is "too hot"?