[TG] [TG11] RS 62157 Cable for A70D - source?

[dave.squared@hotmail.com]

Hi There,
I’m trying to locate a power/NMEA cable with plug for the A70D MFD.
I believe this is part number RS 62157.

I have one that came with the unit which is installed for a deck mounting. I’d like to set up a second mounting location at the chart table with its own plug and cable so that I can use the MFD down below or on deck as I choose.
It would also be good to find an additional surface mount bracket but this is not essential.

I’m not having any luck finding this old cable for sale anywhere.

If you have any suggestions as to where I might be able to purchase this cable or if there is somewhere on the forum where I can list a “wanted” ad, could you please let me know.

I live in Sydney Australia but would be willing to buy from an international seller if needs be.

Regards
Dave

[Tom - Raymarine - Moderator]

Hello Dave,

R62157 is the part you're after (no S), in case you're looking for one online.
I've had a look and we don't have any in stock either here or overseas, but if you're struggling to find one and you can swing by our office in Frenchs Forest at some time in office hours, I think I can find a spare used/test one for you. The address details are at http://www.raymarine.com.au/display/?id=1154.

Regards,
Tom

[dave.squared@hotmail.com]

Hi Tom,
That is so generous of you, as I’ve said before, Raymarine provide the best customer support I’ve ever come across!
I’ve looked everywhere and even offered to buy A50 and A70 MFD’s just to get hold of the cable, they are rare as hen’s teeth.
So I’d definitely like to take you up on the offer of the old test cable if you have one.

Would it be possible to mail the cable out to me?
Getting to French’s Forrest is a bit of drag but I can do it if necessary.
I’d be happy to pay for cable and postage, even if it’s just a donation to the office Christmas party fund!

While I’m stretching the friendship, I don’t suppose you’ve got a spare old mounting bracket lying around anywhere?

Regards, and huge thanks
Dave

[Tom - Raymarine - Moderator]

Hi Dave,

Believe it or not, the limitation on posting it out isn't the postage cost - which would be trivial - but the time, which isn't.
No, sorry, no brackets left, only the cable which would be a no-longer-required test one.
I'll leave it aside in case you get the chance to come by some time.

Regards,
Tom

[dave.squared@hotmail.com]

HI Tom,
That’s fair enough.

Please hang on to the cable and i will certainly drop in early in the week beginning 11 June to collect it. I’m offshore until then.
I was Seriously considering spending US$ 140 to buy an A50 just to get the cable, so it is great that you have one you can spare!

Thanks again.
Regards
Dave

[dave.squared@hotmail.com]

Hi Tom,
Thanks for your time last week. It was good to meet you. As much as the forum is really helpful, a few minutes of conversation gave me a better perspective on how a system should be put together from a data integrity point of view.

In my latest (hopefully last) revision of the layout I have made the following adjustments:
- I have taken your advice and used Seatalk connections wherever possible.
- The only remaining NMEA connections are the 10Hz heading input to the A70D and the interlink to the VHF from the A70D.
- I have added a Double throw power switch such that only the ST2000 pilot OR the 3rd party compass can be powered on at any one time.
- The ST2000 is connected via an unpowered ST connection (red wire not connected) to avoid a power loop (when the tiller pilot is connected and powered up).
- I have made allowance for two mounting/connection locations for the A70D so that I can have it on deck when required or leave it down below when it is not needed on deck. This makes the layout look complicated but it’s not really considering that the A70D cannot be in both locations.

I have some questions for you regarding the proposed layout.

As you can see I have two ST1/STNG converters in the system and I know you are not very keen on this. However, I don’t think thre’s any data loops and I thought this would be better than trying to daisy chain all 8 devices on to one Seatalk bus. This arrangement also reduces the cable run lengths by several meters and makes installation much easier.

Q1: Is it ok to use two converters or should I try to run everything from one?

If I went with one converter instead of two I’d need to put a “T” splice in the Seatalk bus to avoid very long cable runs.
Q2: Is it ok to use “T” splices in a Seatalk bus?

I have read that no more than 5 ST devices should be run from a single ST1/STNG Converter.
Technically, I have 6 devices on my Aft converter (ST60+ Graphic x 2, ST60+ Wind, ST60+ Depth, ST6002 Pilot Controller plus ST2000 Pilot). Only 5 of these are powered from the Converter, the ST2000 Seatalk connection is data only.
Q3: Is it ok to have 5 devices taking power and 6 devices taking data from the single converter?

I could rearrange the layout to have 5 devices on the Fwd Converter (ST60+ Speed, 2 x ST60 Multi, ST60+Wind, ST60+ Graphic) and 4 on the aft converter (ST60+ Graphic, ST60+ Depth, ST6002 Pilot Controller, ST2000 Pilot). However this would increase the length of the cable runs considerably and would involve a lot of extra work.
Q4: Is there any urgent need to redistribute the ST devices or will the proposed layout work ok?

If powering of 8 ST devices from a single converter is a problem, I could avoid this by providing a separate power source to one or other group of them. For example I could make the aft ST/STNG converter cable unpowered and power the 5 aft devices with an external supply.
Q5: What is the best practice for powering a large number of Seatalk devices when ST1/STNG Converter(s) are in the system?

Any other problems/comments with the proposed layout?

Cheers
Dave

[Tom - Raymarine - Moderator]

Hello Dave,

Quote:Q1: Is it ok to use two converters or should I try to run everything from one?

I would always avoid multiple convertors and keep to an absolute minimum the number of separate networks. I would use a single Seatalk network.

Quote:Q2: Is it ok to use “T” splices in a Seatalk bus?

As long as the splices are good (so not the usual not-properly-fused, twist-and-tape horrors that cause fire risks in almost every old Seatalk network I've been unfortunate enough to see), T-junctions are fine. Seatalk is very tolerant of the network layout, a luxury that becomes impractical as networks get faster (NMEA2000.)

Quote:Q3: Is it ok to have 5 devices taking power and 6 devices taking data from the single converter?

There are only fairly narrow PCB tracks inside the ST1-STNG convertor so you shouldn't try to power a big network through it, but the devices you list should be ok.

Quote:Q5: What is the best practice for powering a large number of Seatalk devices when ST1/STNG Converter(s) are in the system?

I don't think we have an established best-practice recommendation for this, but I would have a separate (fused) power on each side (only 1 on each side) of the convertor, with the red wire disconnected on one side or the other of the convertor and a label at the disconnection to make clear to the next person who works on the system why it's disconnected and not to reconnect. Labels are imperative!

Regards,
Tom

[dave.squared@hotmail.com]

Hi Tom,
Thanks for the reply. Very helpful. I have installed the system exactly as you suggested and everything is working beautifully.

I still have a weird one where the ST2000 needs to have a zero variation setting to get the right heading on the other instruments but I think this is because everything is getting variation from the A70D. Both the ST60+ Graphic Displays are indicating that they are “slaves” on the variation setting page.

I will post a layout diagram to show the final arrangement in the next few days. I think it is pretty clean considering the age and combination of equipment and it certainly gives me all the displays and functions that I need.

Many thanks for your help and advice. I remain very impressed with Raymarine’s commitment to customer support, especially considering the age of the gear.

Cheers
Dave

[Tom - Raymarine - Moderator]

No problem Dave, I'm glad it's working well.

Yes, the A70D auto-calculates variation based on position and date, so this takes precedence over the ST2000's manual setup, and only one should be used as you have found.

Regards,
Tom

[dave.squared@hotmail.com]

Hi Tom
Final layout for your information.
Thanks again for all your help and for the A70D cable.
Cheers
Dave.