Rogue MPT-3048 now available
For those who've been waiting, just a heads-up that the 3048 is now available for ordering on the Rogue website. http://www.roguepowertech.com/products/mpt3048.htm If you've visited the page rec...
Forum Discussion
Never heard that gain error is greatest at full scale. Can you provide a link? Are you saying the gain error is nonlinear? The gain is probably set by a couple of resistors connected to the error amp. These resistors are not perfect. They have a tolerance that more or less defines the measurement gain error.
I understand that errors can be divided into gain and offset errors. But you didn't provide a gain and offset error specification.
The whole object of the amp & volt measurement specification is to determine what's the possible error when reading let's say 5.0A. Are you saying it's impossible to determine this error without measuring it? What's the purpose of your spec? What's does 1% at 100A mean? Max current is only 30A.
I'm guessing your current measurement error is at best 3 to 10% of reading plus +/- 0.1A. 0.1A is LSD, not offset.
Sal
I understand that errors can be divided into gain and offset errors. But you didn't provide a gain and offset error specification.
The whole object of the amp & volt measurement specification is to determine what's the possible error when reading let's say 5.0A. Are you saying it's impossible to determine this error without measuring it? What's the purpose of your spec? What's does 1% at 100A mean? Max current is only 30A.
I'm guessing your current measurement error is at best 3 to 10% of reading plus +/- 0.1A. 0.1A is LSD, not offset.
Sal
lorelec wrote:
Full scale error in terms of ADC output (which is what the display derives its measurements from) is the sum of offset error and gain error -- gain error being the greatest at full scale. It's a very common spec. Lots of references on it if you do a Google search.
Error at lower values has typically been observed at a couple tenths of an amp. Don't know if I have an exact spec for you at 5.0A. No one yet has gotten flustered over their ammeter being off by an extra tenth of an amp. Most charge controllers are off by much more that that.
