Fisher vs 4 pins for Shearwater Nerd

[signix]

I disagree price make a difference between a HUD and a Nerd 2 for exemple. It is not high in my decision tree but if one connector is better and cheaper it is all good.
I had a discussion with an instructor who loves his fisher and totally hate the 4 pins connector. I dove with his rebreather and found the connector useful and it looks smaller than the 4 pins.
Before making a move I wanted other opinions and I thank you all for the answers.

I will probably go with the 4 pins because it is a wet connector and based on your posts it looks more reliable.

Thank you

 

[tbone1004]

I disagree price make a difference between a HUD and a Nerd 2 for exemple. It is not high in my decision tree but if one connector is better and cheaper it is all good.
I had a discussion with an instructor who loves his fisher and totally hate the 4 pins connector. I dove with his rebreather and found the connector useful and it looks smaller than the 4 pins.
Before making a move I wanted other opinions and I thank you all for the answers.

I will probably go with the 4 pins because it is a wet connector and based on your posts it looks more reliable.

Thank you

what on earth was his rationale for favoring the fischer cables? it is marginally smaller, but on a ccr that doesn't actually matter.

The only real advantage it has is that you can have a flush bulkhead in a reasonably small space, i.e. the Petrel EXT wouldn't really be possible with the 4-pin cable which would make OC diving with it somewhat annoying.

 

[v101]

My experience w/ fisher ports was like many others on this subject. after my rebreather training class i did some diving on my own, after about the first 3-4 dives, I started having one of my cells act up, thought it was the cable, thought it was the cells, thought it was sun-spots.... anyway after getting everything looked at the only remaining variable was the computer. Sent it back to get looked at and the fisher port needed replaced, a PIN was broken.
about 8 months later it happened again. I took great care to make sure i connected properly, all seemed ok, I have a feeling it was still user error when I reached to DON my stages, i feel it was putting some pressure on the cable/pins and causing some strain.

Anyway went another year and a half no issues, but then started having same issue w/ one of the cells dropping out. if I moved the cable around it would be fine for most of the dive, argg again..... I was removing the computer from my wrist to DON my stages, and that seemed to help...
However a few months back my depth sensor went.... argg. sent back for repair, and told me one of my pins was broke, out of warranty. I went w/. the 4 PIN, I have had zero issues with it, reliable, works, and i dont have to take the computer off to DON my stages.
I personality will not go back to a fisher based computer.

 

[Javarik]

Following up on this interesting discussion, if I want to use my shearwater both for CC and OC dives, is the 4pin connector a viable solution in OC since you must deal with the unattached cable?

 

[Dusty123]

Subcon makes protective ends for them. I dont even think it matters on the 4 pin connectors if they are sealed or not. The 5 pin can-bus ones are a different question but I believe it doesn’t matter on the shearwater end of things since power is coming from the head of the rebreather you arent using if diving oc. I have been told the 5 pin cables will get fried on the canbus power supply pin if they become disconnected in salt water which is the reason for the plastic dodad as opposed to the rubber one....more secure.

 

[v101]

I have the protective caps for the 4 PIN, and dove it OC. I wrap the cable and keep it under a bungee, and it keeps the cable secure from not getting caught on anything. I have not had any problems taking it on OC dives

 

[tbone1004]

Following up on this interesting discussion, if I want to use my shearwater both for CC and OC dives, is the 4pin connector a viable solution in OC since you must deal with the unattached cable?

Subcon makes protective ends for them. I dont even think it matters on the 4 pin connectors if they are sealed or not. The 5 pin can-bus ones are a different question but I believe it doesn’t matter on the shearwater end of things since power is coming from the head of the rebreather you arent using if diving oc. I have been told the 5 pin cables will get fried on the canbus power supply pin if they become disconnected in salt water which is the reason for the plastic dodad as opposed to the rubber one....more secure.

the 4-pin and 5-pin are the same series of connectors, and you want them capped so they don't get scratched/dented. Remember that gold while a very good conductor is not particularly durable so they are very easy to damage.

The only downside to the 4-pin connectors is they don't come with a bulkhead plug like the fischers did so you do have to contend with the cable, but like @v101 said, it's manageable.

 

[stuartv]

My first rEvo came with a Fischer cable to the cells and a Predator EXT for connecting to that cable, for a direct monitor of the cells as a backup to the controller. Eventually, my HUD died and I decided to get a NERD2. I got the Fischer cable version, so I could connect it to the cable that was already installed in the rEvo. And switch to the Predator EXT if the NERD ever died for some reason.

To me, that is the only reason to go with a Fischer cable - if you are going to also have a Predator or Petrel EXT that you would want to be able to use as a backup to the NERD.

Also, since my rEvo already had the Fischer cable <--> O2 sensor cable installed, that made it less expensive AND easier for me, versus switching it over to a 4-pin cable and buying a rEvo-branded NERD2.

If you are starting from scratch, here is what I wish I had known:

Fischer cable path:
NERD2 Fischer is less expensive than a rEvo NERD2
rEvo Fischer cable is stupid expensive (~$250)
"Universal" NERD2 mount that comes with the NERD2 Fischer does not fit on a rEvo DSV or BOV

4-pin cable path:
rEvo NERD2 kit is more expensive
rEvo 4-pin cable is included
Mount to fit rEvo DSV is included

So, in the end, by the time you buy everything you need (starting from scratch), both paths are pretty darn close in price. In my case, it was a bit less to go Fischer, because I already had the expensive cable, and because I bought a rEvo BOV and was able to get the HUD mount that comes with the BOV swapped for a NERD2 mount at no extra cost.

But, for around the same money, I personally would go for the 4-pin setup.

Which I ultimately did. I sold my first rEvo (a Mini) and bought a rEvo Micro. It had no Fischer cable installed. So, before I dived it, I had it serviced and had the rEvo 4-pin <--> O2 sensor cable installed. And I had my NERD2 Fischer converted to a NERD2 with a 4-pin cable.

I do now have a Predator EXT (freshly serviced) and a rEvo Fischer <--> O2 sensor cable sitting around unused, if anybody wants to buy them.

 

[rjack321]

Hi
I am a baby rEvo rebreather diver and I would like to add a Nerd on my unit.
I will try the sidewinder this summer and might have one if I enjoy the unit.
I was looking to an option to keep the computer between the units and was wondering which connector to get.
4 pins connector can be plug underwater which sound good but I see much more fisher connectors and it is a bit cheaper.
What are your experiences on different connectors and do you have any advices ?
Thank you

Fisher cables aren't even waterproof, the orings cannot be serviced, and the pins corrode. Its 20 year old technology which was never even designed to be used underwater.

Unless absolutely forced to use a fischer cable - get the 4pin

 

[azstinger11]

Which I ultimately did. I sold my first rEvo (a Mini) and bought a rEvo Micro. It had no Fischer cable installed. So, before I dived it, I had it serviced and had the rEvo 4-pin <--> O2 sensor cable installed. And I had my NERD2 Fischer converted to a NERD2 with a 4-pin cable.

I do now have a Predator EXT (freshly serviced) and a rEvo Fischer <--> O2 sensor cable sitting around unused, if anybody wants to buy them.

Was Dive-Tronix who did the fischer to 4 pin conversion? I got a really good deal on a NERD2 fischer, so since there isn't currently any cabling might as well upgrade it at the start when I send in the rEvo for its servicing.