Raystar 125 GPS connection query

[Bejasus]

whilst waiting for a reply from Raymarine, I thought I would ask the question on here.
I am trying to sort out crappy installation of E80, ST70's Seatalk ng backbone and Raystar 125 GPS.
Installer ran a power connection from breaker to navpod and fitted terminal blocks, to which he connected E80 power and GPS power feed. He then connected the GPS to the E80 and also into the backbone cable. Why? GPS manual gives instructions for doing each way but doesnt say to connect both and since E80 is connected to the SeaTalk network via the ST70, why would you.
If I connect the GPS to the E80, will the E80 itself not power the GPS?
If not, then if I connect it to the Seatalk backbone cable, should this not power the GPS without need to resort to a seperate power connection? Also then the E80 should pick up the signal.
It seems to make more sense to me to connect to the E80 since it changes the nmea output to match the AIS250. I am just concerned about conflicts or missing data.

Anyone any ideas?

 

[hightech]

You only need seperate power feed for the 125 if you intend to run it as a NME0183 device. Normally you would install it as seatalk with power coming from the bus.

As it is wired, the seatalk bus would stay live all the time the breaker was on, so the gps and any instruments would be active with the plotter turned off. I suppose you could limit current by doing this, but kinda defeats having the plotter in the fist place.

Any installs I do are via Seatalk to the bus then local wiring of the AIS250 for the hi-speed nmea that requires.

 

[Bejasus]

thanks hightech, one of the depiction in the Raystar book says exactly this, but also depicts a direct connection to the E80, but I am assuming that this would be only if you were using the E80 as a standalone unit. I will give it a go and see if I am missing anything.

 

[pvb]

The correct way to wire the Raystar 125, according to Raymarine, is to power it from the main SeaTalk bus, not from the E80. So, the connections should be:-
* The Raystar red and green wires would connect to the SeaTalk bus red wire (which should be powered from a fused 12v+ feed).
* The Raystar yellow wire should connect to the E80 SeaTalk lead's yellow wire and to the SeaTalk bus yellow wire.
* The Raystar black and brown wires should connect to the E80 SeaTalk lead's black wire and to the SeaTalk bus shield (which should be connected to 12v-).

Raymarine's reason for not powering the Raystar from the E80 is to avoid loss of fix due to low voltage.