The Petrel is a robust dive computer for technical divers of all levels, and ready out of the box for air, nitrox, and trimix gasses. The Petrel can be used for open-circuit and closed-circuit diving, as well as gauge mode if desired - no pin upgrades are needed. External PO2 Monitoring
The Petrel EXT features a Fischer connector for monitoring of 1 or 3 external oxygen sensors on any rebreather equipped with a 7-PIN Fischer Cable. (The Petrel will not support 2 sensor configurations.) Closed-circuit divers using a Petrel EXT can choose between using the external oxygen cells, or a user-defined set-point for decompression calculation. Decompression Algorithm
Shearwater dive computers use B_hlmann ZHL-16C with Gradient Factors as the decompression algorithm. User adjustable conservatism can be done by manipulating the gradient factors. An optional VPM-B algorithm may be purchased if desired.
A unique 'tissues' display gives a wonderful graphical representation of your tissue loading while diving. For more information, see the great video from Shearwater here
The 2.4" Color LCD display is easy to read, with high contrast, and automatic screen brightness. The display may be customized with user-defined font colors, and may be inverted for those who wish to wear the Petrel on their opposite arm. User Interface
The user interface is simple to use with adaptive menus. Commands are entered with piezoelectric buttons. Warnings are clear and concise using color-coded warnings. A simple 2-button bailout allows for quick and easy changes to open-circuit. No confusing icons are used, rather the Petrel navigation is done with plain-language. Divers have a choice of metric, or imperial units.
Banks of up to 5 open-circuit and 5 closed-circuit gasses may be saved, and turned on and off as needed. Underwater, gasses may be added, removed, or changed should any unplanned events occur. Battery
The Petrel features a single battery compartment, which will support the use of any AA-sized battery. Shearwater Research recommends the use of Duracell Coppertop alkaline batteries for their widespread availability, and reliability. The Petrel will operate about 35 hours on a quality alkaline battery. Saft LS14500 batteries used by the Shearwater Predator can also be used, and offer the longest life - about 90 hours on the medium brightness setting. Li-Ion, NiMH, Photo Lithium 1.5 and Zinc-Carbon 1.5 batteries can also be used.
The Shearwater Petrel also features a super-capacitor to keep track of your tissue loading in the event a battery change is required between dives. This capacitor holds enough energy to maintain tissue status for 15 minutes. This means that if your battery change takes less than 15 minutes you can continue with repetitive dives. Additionally, you will not need to set the date or time as the Petrel will have remembered it.Dive Logging
The Petrel features a 1000 hour dive log, which may be downloaded to a free Shearwater Desktop Software via a wireless bluetooth connection. The bluetooth can also be used to upload firm wear updates, when available.