Vision 4th Cell Holder Experiences

Installation Experiences with th Vision 4th Cell Holder
By Paul Buskermolen


After diving my own narkedat90 cell-holder for some dives now (and very satisfied with it) I had 2 buddies wanting one also. Unlike me they went for the full package with the cable. After missing the X-mass shipping deadline I finally received the cell-holders this week. And as with mine it looked perfect (if I may say even better than the original). Following are my experiences fitting the cell-holder to the Vision head of my Buddy

The package contained the cell-holder, an end-cap for the connector and a cable with cable gland and SMB connector.


First step is to get the cage over the cells off and remove the cells as if you where to swap them out for new ones. Than you will have to remove the retaining nut on the top of the head keeping the old cellholder in place. If you don’t have the official box-spanner for this you can also try to gently tap it loose with a screwdriver on the little notches in the nut.


You can now remove the old cell-holder, but be careful as the battery box is still connected to the cell-holder. Than remove the battery box from the cell-holder by un-screwing it through one of the holes that are now open as the cells are removed (if you prefer you can also do this BEFORE removing the retainer nut). You now have the separate cell-holder, a spacer, the battery box and the rest of your Vision head.


Now you can start rebuilding your head with the new cell-holder. First thing to do is to reconnect the battery box to the cell-holder. I found it easiest to first place the screw and spacer and then manoeuvre the battery box over the screw to fasten it.


Following is to re-insert the cellholder in the head. There are 2 things that are important here.

• Ensure that the o-ring on the inside of the head around the hole for the cell-holder stays in place.
• Turn the cell-holder such that it fits the indentations in the hole. The cell-holder should be perfectly straight. If it isn’t straight in the hole, turn it till it slips correctly in the indentations (the straight edge in the hole).
• When the cell-holder is positioned right you can replace the retaining nut again to secure the cell-holder in place. At this stage you can also place all cells and reconnect the 3 main-cells (at least this frees you from the dangling wires).

At this point you are basically just as far as you started, a vision head with 3 connected cells. Now the fun begins to expand your Vision head capabilities with the 4th cell.

When looking at the way the cable gland was delivered I had my doubts as there was no o-ring to seal the gland at the side of the cell-holder. An email to John confirmed that this was a self sealing cable-gland. As he’s the designer of the thing I had to give him the benefit of the doubt and placed the gland without an o-ring (which worked out fine seeing the successful pos and neg tests after this exercise).

To get the cable placed I found it useful to remove the cable-strain part of the gland so I could still move the cable around. You have to pull the cable (SMB side) through the side hole on the top of the head and let it come out on the side hole next to the cells. Now you can screw in the cable gland (without the cable strain part) and fastened slightly. Be careful not to overdo this as it’s easy to over tighten and shave the thread of the gland.


There are now just 3 things left to do

• Pull the cable through the holes till you have the desired length to reach your 4th cell
• Connect your cable to the 4th cell
• Place the cable strain and tighten by hand securely. This will not only secure the cable but also seal the gland around the cable.

And than off course the moment of truth, will it work. I’ve connected a VR3 to see if it worked and (surprise, surprise) we got a reading.


Most important after having done all of the above is to do a pos and neg check with a build-up breather to check EVERYTHING is airtight.

The whole rebuild took me ½ an hour and is pretty straight forward if you think your way through. I have had some dives now with my cell-holder and apart from knowing now that the cell I’m using is degrading over time during the dive I am really satisfied with it.

I can only say that this is a superbly machined Rebreather gadget which I can recommend to anyone who’s looking for a 4th cell in his/her system. I found both building quality AND service far above average ... have a look at narkedat90 for the info on this nice peice of kit.

Paul Buskermolen


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