Shearwater Petrel 3 Fischer Dive Computer

The Shearwater Petrel 3 Fischer is a technical and rebreather dive computer defined by its Fischer port connection, dedicated to the wired link of a rebreather's oxygen cells. This version carries over the proven electronics and firmware of the Petrel 3 family and clearly steers its use towards monitored closed-circuit diving.

Fischer port connection and external PPO2 monitoring

The Fischer port connection is the distinguishing element of this model. It feeds the External Monitoring Mode (CC EXT), which provides real-time PPO2 monitoring for 1 to 3 oxygen sensors in closed circuit. The SCR EXT mode extends this monitoring to semi-closed circuit, again for 1 to 3 sensors. The diver thus gets a direct, continuous reading of the breathing loop oximetry.

Protected AMOLED display

The AMOLED display measures 6,60 cm on the diagonal (2,6 inches) with a 320 x 240 resolution. It is protected by a toughened glass lens and framed by a titanium bezel. Operation runs through piezo touch buttons, with no moving part exposed to pressure.

Depth, gases and algorithm

Rated depth reaches 290 m. The Petrel 3 Fischer handles up to 5 gases in open circuit and 5 gases in closed circuit, and stays compatible with air, nitrox and trimix. It covers Air, Nitrox, Nitrox 3 gas, OC Tec (multi-gas trimix decompression), CC/BO (fixed PPO2 in closed circuit) and Gauge modes. Decompression relies on the Bühlmann GF algorithm, with optional VPM-B and DCIEM. A fast switch from closed circuit to open circuit eases bailout management.

Air integration and alerts

Air integration is offered as an option: the computer pairs with up to 4 wireless transmitters to track the pressure of several cylinders, from open circuit to bailout gas. A strong vibration alert system reinforces the perception of warnings. A 3-axis tilt-compensated digital compass completes navigation.

Power and battery life

The unit runs on a single user-changeable AA battery, any type accepted, for a capacity of about 5,25 Wh. Battery life depends on the cell: up to 60 hours with a 1,5 V lithium, up to 40 hours with an AA alkaline and up to 100 hours with a Saft LS14500. The recommended and supplied battery is an Energizer Ultimate Lithium AA. Product weight is 115 g for overall dimensions of 130 x 105 x 70 mm.

Logbook, connectivity and box contents

The dive logbook offers a capacity of about 1 000 hours of recording. Bluetooth connectivity handles dive transfer and upgradeable firmware updates. The box contains the Petrel 3 dive computer with Fischer connection, an inspection control card, a product information guide, a screen protector and a black webbing strap (double).

Manufacturer

The Petrel 3 Fischer is designed and built in Canada by Shearwater Research. Manufacturer reference: SH11302.