Tracking maintenance

[688ClassRebreather]

How do you track required maintenance on all your gear? With about a dozen tanks needing VIPs and Hydros, about as many regs requiring service, two rebeathers and all the O2 cells that need to be replaced, my Excel spreadsheet is working overtime to keep track of it. There must be a better way out there that I have not found.

 

[tbone1004]

excel is about as good as I have found. Maybe with @Shearwater Cloud coming out, they can put some sort of tracker into the handsets where you can list dates of cell installs etc, but I think it would be just as clunky if not more so than excel

 

[chris kippax]

Another vote for Excel

 

[fsardone]

Filemaker relational database tracking dives and deadlines, also tracking voltages of sensor over time. It takes a bit but once is set up it automates everything and also allows to track how many dive hours are logged on each item. Which might be relevant for rebreather sensors.

It can be done with freeware tools (postrgres sql with php5 front end) but requires way more effort and programming skills than filemaker or access.

Lacking programming skills, I vote for excel

 

[kensuf]

AI and Shearwater are coming up with a little magic to make cell tracking easier. Meanwhile, I check linearity between air and 100% on the cells pre-dive, and follow-up with an O2 flush to check linearity and current limiting up to 1.6 at 20 fsw during the dive. Any cell that doesn't fall within my tolerance limit for linearity gets replaced.

 

[joshk]

Excel is fine for some stuff, but for tracking gear, maintenance, cells, tanks, etc, I setup a few tables on Airtable. My favorite thing is the relational aspect. Much like @fsardone's Filemaker system, you can setup a table for all your gear, and another for maintenance times. I have a table of cells and another “cell log” table where I enter various values and link them back to each cell. Dive logs, reg service intervals, and tanks all work similarly.

 

[uncfnp]

Not sure if it will help with tracking your rebreather info but for your general gear there is a section in the app Dive Log for tracking gear. Purchase date, price, location, seriel number. Service date, next service, O2 service. A comment area and can even include a photo for record keeping.

I would be surprised if other dive logs do not have this feature.

 

[DA Aquamaster]

O2 cells:

I wasn't satisfied with the linearity check on 02 at 20 ft and started using a DE-OX cell checker. I'll check them periodically and note the changes over time. Once I start to see either differences between the actual PPO and the displayed PPO2 at 1.3, or excessively long response times, the cell gets retired.

Tanks:

We currently have 38 tanks including primary sidemount and back mount tanks, stage bottles, O2 bottles and rebreather bottles, plus some that are used for O2 storage and a half dozen tanks that are on loan at the moment. They are fairly evenly spaced out regarding hydro test. It's not hard to keep track of what is due for hydro with the active tanks - it's a bit harder with the inactive tanks or with tanks that we store in FL.

Regulators:

Between two divers with back mount, sidemount, dil, O2 and stage regs, we have a lot of regs to keep track of. The less used regs (back mount regs, sidemount regs, and some of the stage regs) are inspected before a trip where they will be used and are serviced based on condition. With good selection of the design, decent post dive maintenance, proper storage, and thorough condition inspection regulators, and in particular first stages, can have a long shelf life. The more heavily used regs are serviced annually or more often, again based on condition.

----

I guess in short, I focus as much on inspection as I do preventative maintenance and reserve the service work for when a condition inspection shows need.

I have no idea what people do in similar situations if they are not doing their own tank, regulator and rebreather inspection and maintenance. I suspect they have more failures. I personally would never want to rely on a calendar to tell me when something needs to be maintained. Not all cells are created equally and not all regulators will go a full year between services - especially when used frequently and in demanding conditions.

 

[joshk]

Once I start to see either differences between the actual PPO and the displayed PPO2 at 1.3

What is the “actual PPO[2]” and “displayed PPO2” you're referencing?

 

[tbone1004]

What is the “actual PPO[2]” and “displayed PPO2” you're referencing?

when rebreather cells start to go wonky and get limited, the actual ppo2 may be 1.5, but the cell will only give a mV value that correlates to 1.3. Once that happens, the cell is no longer capable of displaying accurate information and the cells have to be discarded because it could just as easily display 1.1 and you could have 1.7 or more in the loop.

Annoyingly, cell checkers are VERY expensive, with the cheapest being about $400, and the one that @DA Aquamaster is about $1500 so most divers check for that at the start of the dive since there is no easy way to pressurize most rebreathers. CCR Liberty is the only one that I know of that can actually perform cell checks up to at least 1.7 with their checker kit and display all of that information to you as part of your calibration process which is awesome