can a PG500R be powered from Data 2 or 3



I think I read somewhere that Data 1 cannot really power many accessories but I don't recall reading what the capabilities for Data 2 and 3 are. Could I power a PG500R heading sensor from Data 2 or 3? It would seem that the PG500R should power up any time the MFD is powered on so this seems like the way it should go. If you had a separate power feed and switch you could forget to turn it on along with the MFD and not get the results you are expecting.
The spec in the PG500 manual is 0.12-0.03 A (120mA-30mA). The spec in the NN3D manual for the 12V supply on the included 18-pin cable (Data 2&3 plus others) is for 100mA max, so technically you shouldn't do it although I would guess that 20mA over is unlikely to cause a problem.

The alternative would be using a Data1 cable (optional purchase). It is recommended for the BBWGPS GPS module, which consumes 100ma @ 12VDC, so again at least close but possibly even greater supply. Somewhat annoyingly, I cannot find a spec for the max current on Data1 in any of the manuals (NN3D Installation, MFD8/12 Installation, MFD8/12 Operator Manual) so I would just say that it is at least as good as the Data 2/3 cable.

If it were me I would use the included cable (Data 2/3) and expect it to work well: 20% over is not likely to cause a problem.

Perhaps one of the Furuno guys can weigh in on that.

The 100mA spec for the GPS came from the web page; the manual calls for 105-55mA. So now the difference for Data2/3 is down to 15mA - and that is for the maximum current of 120mA for the PG500. With the minimum of 30mA the average will be below the 100mA available; the 120mA is probably just a transient reading, for instance during startup. I would feel comfortable using Data2/3, but it's not my warranty so probably best to hear an official Furuno position.

It is not recommend to use the unit as a power supply for the PG500R. As Greg stated, the MFD doesn't offer enough amps to properly ensure PG500R operations.
Thanks for the replies. I guess I will power the PG500R from the same breaker as the MFD so that they both power up at the same time. Not much point adding those power wires from Data 1 and 2 to my terminal strip considering the low power handling capability. Will simplify the wiring a bit. The MFD and radar worked well this past weekend so I have happy with that .
If you are willing to do a little electrical work you can still have the GPS powered on/off without using the breaker. Go to Radio Shack or similar and buy a small 12VDC relay - make sure the current draw is less than 100mA - and power the relay with the 12VDC from the data cable and use the contacts to switch the power for the PG500R.