RB Guardian FAQ
Q: Does the RB Guardian interfere with my rebreather? A: It was designed to produce negligible loading on any cells/electronics it is connected to. Tests so far performed show that it does not affect gauge readings when plugged in or removed.
Q: What happens if the cells connector floods? A: By introducing a resistor into the cells signal path inside the rebreather, a catastrophic connector flood with worst-case cells shorted results in only a small increase in the cells loading. Tests so far show no impact on an Inspiration's gauge readings and a reduction in gauge reading of 0.001bar on a KISS.
Q: How do I know if my rebreather is compatible with your RB Guardian? A: The RB Guardian has been designed to be compatible with a large range of oxygen cells and to not load electronics. Checking compatibility involves specifying your cell type and asking Underwater Experiences if it can be configured to work with that cell. Additional information about the cells loading may also be required.
Q: What factors affect the RB Guardian's accuracy? A: The design accuracy is within 0.03 bar over the operating range. There are two main factors affecting its ability to perform within this specification. The first depends on the match between the oxygen purity actually used in the rebreather and that which the RB Guardian is set to. Typically the RB Guardian is set to expect 100%. For each percentage point difference between expected and actual Oxygen purity, there will be an additional error of 1% in the RB Guardian's thresholds: for instance, at 1.3 bar, the additional error will be about 0.013 bar.
The second factor is ambient air pressure. The RB Guardian is set as standard to expect 1000mbar. For every 10mbar difference from this, the accuracy will be reduced by 1% of pp02.
Q: Is it possible to configure the RB Guardian to accept oxygen purities other than 100%? A: Yes, please contact us for more information, because this is not user configurable.
Q: Is it possible to take the actual ambient pressure of air into account when calibrating the RB Guardian? A: Yes, please contact us for more information, because this is not user configurable.
Q: Can I use the RB Guardian with only a single oxygen cell? A: Yes, the RB Guardian Works with a single cell but will only function as an advisory HUD and not a Primary in this case. It is possible to fit the RB Guardian where there is a fourth cell and to attach it to that cell. Please contact us for more information.
Q: How do I calibrate the RB Guardian? A: Just press the button on the front of the unit at the moment when your rebreather does its own calibration.
Q: How do I connect the RB Guardian to my rebreather? A: The RB Guardian will need access to the oxygen cells. This is usually provided by drilling an access hole in the vicinity of the cells such that a connector can be added to enable the external HUD to be connected to the internal cells. (Note: This site shows a method for connceting into an Inspiration Classic without drilling holes.) The cells can usually be connected to by 'T' pieces, which ensure that the existing rebreather wiring requires no modification—it's just a case of unplugging and replugging connectors. Please contact us for detailed information as to how this can be achieved and for information regarding how we can help you with this if you require connection components. It is recommended that a resistor is incorporated into each cell signal line as part of the connection components. This helps avoid any external connection flood affecting the rebreather performance.
Q: If I connect the RB Guardian into a CE-approved rebreather, will this affect my CE certification status? A: Yes. The RB Guardian has been designed for compatibility with most rebreathers. As a component, there are no certification standards and as such, to maintain the rebreather's CE status, it would have to be separately approved for each CE certified rebreather with a specific connection mechanism, in which case it is no longer a generic component. If you want to connect it into a rebreather with CE approvals, you will invalidate that approval and will be responsible for the integrity of the resulting system.