OSTC with CCR Fisher Plug

[Tingsten]

Hello OSTC users,

is there a plug&play solution for connecting any OSTC to a CCR equiped with the "STD" ficher plug?!

I do have an OSTC 3 and a mccr Triton (with the Fisher) and I would really love to connect it. My understanding is that the PPO2 monitor unit is using a S8 connector.

I know that the Fisher isn't that reliable so is there any way to change it with a S8 connector?!

Thx you for your help.
Tingsten

[Ralph]

Hi,

you can use the "ppO2 Monitor" to read the analog sensor signals, convert them into digital format and then forward them via the optical link to your OSTC3.
Pro: the optical Connection can be plugged/unplugged wet, to you can get in and out of your rebreather without needed to take the OSTC from your arm.
Con: the ppO2 Monitor is an extra piece of electronics with it's own display you probably don't need and it has it's own battery.

If you would use the OSTC cR, you would not need the extra electronics as the cR has built-in analog inputs.
Con: new computer, more expensive than ppO2 Monitor + optical cable, no wet disconnect.
Pro: less complex (less parts), the cR has a much bigger battery yielding much more runtime.

In both cases you need to hook your O2 cells to the S8 cable. The S8 cable is quite long and comes with an open end. It's very sturdy yet flexible.
So you can either fit a Fischer connector or you can route it directly into the head, omitting an extra Fischer.

BR
Ralph

[Tingsten]

Hello Ralph and thx you for your answer.

I really like the first solution. However, since the Triton head is potted (and thus it is easy to change the cable) do you think it is possible to change my Fisher plug into a S8 plug?
keeping the extra fisher connection is probably not the most reliable solution.

Is the S8 cable included with thePPO2 monitor when you buy it?! Could i just remove and use the connector or is it potted?!

Thx you a lot,
Rémi

[heinrichsweikamp]

The S8 connector is designed to work with the specific cable we use. It's not so easy to attach this connector to a different cable diameter. I would not recommend it, sorry.

regards,
Matthias

[Tingsten]

I'll check the size of the Triton câbles (but it is probably slightly bigger than 6mm).
Otherwise i'll need to go with the extra femalle Fisher attached to the S8 câble (so lots of possible failure points).....

[Ralph]

In case the diameter of your cable is too big to fit into the S8 connector, one last possibility to avoid the Fischer is to strip the outer cable jacket where the S8 glant will go and then use one or more layers of heat shrink sleeves with pre-applied glue on the inside (important!) to bring it to target diameter. Then outside the glant put more sleeves over the junction with the original jacket to restore bend protection. Do let the sleeves end staggered to give it a smooth transition of bending stiffness.
This technique will also work if your cable is too small in diameter - just put sleeves on top of the original jacket.

[Tingsten]

Hello Ralph, hello Matthias,

The Triton has a 5mm cable with a quite stiff insulation layer. If too small adding a heat shrink sleeve (with glue for stopping water entrance) may do the job.
So I'll need to order the PPO2 monitor+Optical cable (+ an S8 connector?).

Thx you again for your help,
Rémi

[heinrichsweikamp]

Hi Rémi,

If you are sure you can assemble this connector (Which involves soldering), yes. this is what you need.

regards,
Matthias

[heinrichsweikamp]

If you want to order, please contact us directly: info@heinrichsweikamp.com please.

regards,
Matthias

[Tingsten]

Hello OSTC TEAM,

do you have the PINOUT for the S8 connector?!

THx you a lot,
Rémi

[heinrichsweikamp]

Sure (It's attached).

There is also information in the manual you got with your unit.

regards,
Matthias

[Tingsten]

Hello OSTC Team,

After 3 dives with this new system that went smoothly, i had an issue today with no link between the OSTC and the PPO2 Monitor unit. The PPO2 Monitor is reading properly the 3 cells but the OSCT isn't reporting any cell value (keep --- for the 3 cells.)

Try to verify the optical cable but i don't see obvious issue (light seems to pass ).
Any idea what to do/verify? Iam runn ing 3.01 firmware


Thx you for your help,
Rémi

[Ralph]

Hi Rémi,

did you use 3.01 firmware on the dives where it worked, too? Just to narrow in on the root cause of the failure...

Ralph

[Tingsten]

Hello Ralph,

I doubt it is a software issue since I was diving saturday with the exact same conf.
I haven't try to downgrade to verify if it works with an older firmware.

Rémi

[Ralph]

Don't downgrade then! If it works / works not with the same FW it's something else...

[Tingsten]

Not sure if this can help but the inner grey part of the optical cable was rotating (freely) on both side of the cable. So I turned it (screwing it) until it is fully locked. Unfortunatly i didn't change the behavior....
I also took some macro pictures of the optical part. It isnt very clean (see picture attached). Not sure if thi can explain the issue?

[heinrichsweikamp]

Hi,

This looks quite crusty indeed. Is there still going light through the cable? You can try holding the ppO2 Monitor without the cable in front of the sensor.

regards,
Matthias

[Tingsten]

Yes light is passing through. Indeed I was wondering if I should get connection between the OSTC and the ppo2 monitor when aligning the emitter and receiver together. I need to try again and see.

Rémi

[Tingsten]

By checking with the zooming camera I have I can confirm that the PPO2 Monitoring is flashing at 1Hz. When I put the cable i am not able to see the light at the output (it might be difficult)...
Allthough i don't get any good result by putting ostc and ppo2 monitoring unit very close together i guess and hope it is just a cable issue.

I'll try to clean the cable and or reassemble the connectors?!

Rémi

[Tingsten]

Hello,

After reworking the optical cable there was no change (despite the fact that the cable was very clear).
So I decide to downgrade the firmware to 3.00 and i now have the connection.

So not sure if the issue if 3.01 or after few dive the 3.00 will also do the same. Need to be checked.

Rémi

[Tingsten]

Hello OSTC Team,

After around 10 dives with the system, i can confirm the following :
-every 3 dives the computer doesn't connect anymore with the ppo2 monitoring (it doesn't see the cell)
-Reinstalling the firmware allaways immediatly fix the issue
-I do have the same issue with 3.00

Thx you for your help,
Rémi

[Ralph]

Hmm... May you do us a favor: next time it doesn't work any more, just do a reboot from the reset menu instead of re-installing the firmware. If that unblocks it as well, we are able to narrow thing further down.

Thanks a lot,
Ralph

[Tingsten]

OK i'll try that and tell you.
Rémi