Renogy DC-DC Test Results-UPDATE 4 (Better!)
Updates 23 June--new test with Renogy input exposed for voltage readings Update 25 June more readings Update 4 - 27 June-- fewer amps with fat wire were noted this time! ----- I have the 20 ampe...
Forum Discussion
So forced into a new test by otrfun, this time all fat wire pos and neg input and with and without the ammeter inserted:
No ammeter:
Input- 13.62v x ? amps
Output- 12.60v x 20 amps = 252w
With ammeter (grads are 0, 10, 20, 30 etc to 60a with fat needle small space between 10 amps marks) also truck engine bay getting hot so lower engine batt voltage too:
Input-12.82 x 26ish amps = 333w
Output-12.56 x 20 = 251w
251/333 = 75%
So that looks more like what to expect within margins of error. Thanks all for keeping me at it, so the results make more sense.
Just how much installation upgrades are "worth it" is hard to say, once you get max output steady. Some wiring improvements are easy and worth it, while some are harder and maybe not. It also depends on your whole set-up for opportunities for wiring routes etc.
EDIT-- using Salvo's methods from way back, I have tried to get the amps with the first case where there was no ammeter.
First get the R of the connection with the ammeter showing 26 amps and voltage drop of .96 from truck to Renogy, R = 0.96/26 = 0.03692, so with voltage drop no ammeter at 0.88, and same R, amps would be
0.88/0.03692 = 23.8 amps which seems about right, and
13.62 x 23.8 = 324w, and 252/324 = 78%, which also works.
All numbers are approx but IMO within the ball park for showing how the Renogy operates.
No ammeter:
Input- 13.62v x ? amps
Output- 12.60v x 20 amps = 252w
With ammeter (grads are 0, 10, 20, 30 etc to 60a with fat needle small space between 10 amps marks) also truck engine bay getting hot so lower engine batt voltage too:
Input-12.82 x 26ish amps = 333w
Output-12.56 x 20 = 251w
251/333 = 75%
So that looks more like what to expect within margins of error. Thanks all for keeping me at it, so the results make more sense.
Just how much installation upgrades are "worth it" is hard to say, once you get max output steady. Some wiring improvements are easy and worth it, while some are harder and maybe not. It also depends on your whole set-up for opportunities for wiring routes etc.
EDIT-- using Salvo's methods from way back, I have tried to get the amps with the first case where there was no ammeter.
First get the R of the connection with the ammeter showing 26 amps and voltage drop of .96 from truck to Renogy, R = 0.96/26 = 0.03692, so with voltage drop no ammeter at 0.88, and same R, amps would be
0.88/0.03692 = 23.8 amps which seems about right, and
13.62 x 23.8 = 324w, and 252/324 = 78%, which also works.
All numbers are approx but IMO within the ball park for showing how the Renogy operates.
