Citizen Promaster Divers 1000m watch

https://www.firstclasswatches.co.uk/citizen-promaster-marine-1000m-divers-bn7020-17e-p-41321/

Citizen Promaster Divers has taken a step into unexplored territory. PROMASTER Eco-Drive Professional Diver 1000m is the world’s first* watch to combine Citizen’s propietary Eco-Drive technology with 1,000 metre saturation diving performance. Powered by light, the watch is built to withstand the relentless water pressure experienced by saturation divers at 1,000 metres beneath the sea. It’s an example of Citizen’s techinques and technology opening up new frontiers.
*As of February 2017, according to research by Citizen Watch Co. Ltd

Alright to exclude helium

Helium is the greatest obstacle when designed a light -powered watch for saturation diving environment. Helium gas molecules are so small that they can easily penetrate the inside of a water resistant watch. The helium then drives up the interior pressure of the case, risking damage to the glass and to the movement. The watch must be sealed to keep helium penetration to a minimum. Citizen exhaustively performance test every aspect of the Eco-Drive professional Diver 1000m – its structure, materials, assembly technique and so on – to achieve both water resistance and helium resistance (mixed-gas resistance) as a depth of 1,000 metres. This is a world first for a light-powered watch.

Specifications you can trust through strict helium pressure testing

Citizen subject the Eco-Drive Professional Diver 1000m to helium pressure testing under all sorts of scenarios – when it was new, after long use and even after servicing. Based on these tests Citizen created a structure that would maintain the right pressure to prevent damage to the movement while, of course enabling the watch to display the right time. Among the safety features is an escape valve, which automatically opens and shuts according to the internal pressure of the watch, Driven by a combination of know-how and passion, Citizen’s engineers experimented with many different structures and materials before achieving the watch’s final robust specifications.

Deep-sea verification and validation tests in cooperation with JAMSTEC

Citizen conducted verification and validation testing with the cooperation of JAMSTEC (Japan Agency for Marine-Earth Science and Technology) during the product development process of the Eco-Drive Professional Diver 1000m. The product prototype was attached to a basket on a manned submersible, Shinkai6500, to leak test is and to examine the effects of high water pressure. Citizen confirmed that the watch keeps running at depths for greater then 1,000 metres. Through these tests, Citizen demonstrated that the Eco-Drive Professional Diver 1000m is a diver’s watch with extraordinary levels or reliability.

JAMSTEC is a national research and development agency under the Ministry of Education. Culture, Sports, Science and Technology. It contributes to the advancement of academic research and improvement of marine science and technology through basic research and development based on ideals of peace and human welfare.

Durability thanks to Citizen’s proprietary surface-hardening technologies

Citizen made extensive use of the proprietry surface-hardening technology Duratect MRK to ensure that the Eco-Drive Professional Diver 1000m can withstand the water pressure at depths of 1,000 metres. By applying Duratect MRK to the case when parts like the crown tube and the escape valve tube were already in place, they bonded the individual components to the case at the atomic level to achieve a higher level of adhesion. The result was not just a tougher case surface but durability capable of withstanding 1,000 metres of water pressure.

Where technique shades into art

The Eco-Drive Professional Diver 1000m is assembled by Citizens skilled craftsmen. They assigned a team of experts to the job of manually assembling the glass and case of the Eco-Drive Professional Diver 1000m. This is in fact the reason why they only produce 35 units a day. The craftsmen go about their work in a dust-proof cleanroom with the different components in front of them. The hardest task – closer to art than anything else – is attaching the glass to the case without it snagging on the rubber seal. This model is a work of art that can only be produced by hand, the culmination of Citizen’s technologies and techniques as a true manufacture g’horlogerie.

Lightweight. Rust resistant. Scratch resistant.

Super Titanium

Light, kind to the skin and resistant to rust, titanium has excellent natural properties, At the same time, though its softness and viscosity make it very hard to process. Through processing technologies developed over decades Citizen have managed to create beautiful mirror finishes and clean sharp edges. And by applying their proprietary surface-hardening technology, Duratect, they created Super Titanium, a material over five times harder than stainless steel. super Titanium resists nicks and scratches even in the harsh environments experienced by divers and climbers. Uniquely for Citizen Promaster Divers watch Citizen developed models that combine two technologies – Duratect MRK and Duratect DLC – for Citizens toughest exteriors yet.

Cold Plasma Coating: Duratect DLC

Duratect DLC (diamond-like carbon) is a cold plasma technology. It involves passing an electric current through hydrogen and carbon gases to diffuse an amorphous carbon coating onto the surface of the titanium. The DLC coating has an amorphous structure coating carbon and hydrogen (like a diamond) and lacking any grain boundaries. As a result, its extremely hard, smooth and scratch-resistant. Citizen’s duratect DLC also has a higher level of adhesiveness than standard DLC technologies.

Gass hardening: Duratect MRK

Duratect MRK is a technology that maintains titanium’s original properties of lightness and rust-resistance while hardening the surface of the material itself. Two gases are injected into a special vacuum furnace and heat treatment applied to produce a hard layer on the surface of the titanium. Resistance to nicks is increased because the surface of the titanium material itself is made harder. Whether you’re hefting compressed air tanks out at sea or clambering up a rocks mountain summits, Super Titanium will protect your watch from all the shocks that harsh environments bring.

Shock counteraction function

Whether you’re at sea, on land or up in the sky, any obstacle-rich environment comes with the risk of bumping your Citizen Promaster Divers watch and knocking the hands out of place. Citizen developed its propriety shock counteraction function to address that problem. The instant you watch experiences a shock or strong vibration, an electrical signal is sent to the motor, momentarily locking the rotor to prevent the hands from moving out of place. The whole operation takes just one-thousandth of a second, meaning that the watch has prevented any deviation and resumed telling the right time before you’ve even noticed the impact! A professional sports watch must display the correct time regardless of extreme conditions. That’s why the shock counteraction function is so valuable.

Automatic hand correction function

This function goes into action in the unlikely event of the hands deviating from the correct time. It checks the position of the hands at regular intervals and automatically returns the hands to the correct position in the event of any error Combining this function with the shock counteraction function means that your watch maintains its accuracy even in environments where exposure to shocks and bumps is high.

Luminous hands and dial

Citizen Promaster Divers photo-luminescent markings absorb light fast and stay bright for a long time. We made sure that a generous proportion of the hands is coated in luminous material and tested a range of colours before selecting the most visible ones. You can be confident that your watch is fully readable even in the darkest depths of the ocean.

Screwdown crown

A screwdown crown helps makesCitizen Promaster Divers fully water resistant. Because the stem of the crown is threaded, it can be screwed tightly into place when not in use. Locking the crown doesn’t just mean better water resistance, it also guards against unintentional rotation.

Unidirectional bezel

Citizen made the bezel of the Citizen Promaster Divers unidirectional in line with the ISO standard of diving watches. This improves the safety by eliminating the danger of a diver accidentally turning the bezel the wrong way during a dive. The Eco-Drive Professional Diver 1000m model is equipped with a bezel-locking mechanism.

Double-folding buckle

Using a double-folding buckle means that hard-working professionals can concentrate on the task at hand without having to worry about their watch accidentally slipping off. It’s the most basic safety measure of all.

Altimeter and Compass

Citizen Promaster Divers altimeter can measure from minus 300 metres to 10,000 metres above sea level – higher than any mountain on earth! Once activated, the altimeter continuously measures your altitude for five minutes, then provides automatic readings every three minutes  over the next 12 hours, freeing climbers to focus on climbing without the need to perform any fiddly manual operations. With all the information displayed in analogue rather than digital format, there is no need to switch away from the all-important time display to check altitude or orientation.

Cold proof to minus 20 OC

When you’re exposed to a raging wind on the summit of a mountain, you can experience unimaginable levels of cold. But however severe the conditions, climbers need access to time and altitude information. For the Citizen Promaster Divers they recreated an ultra-cold environment in which to conduct a barrage of verification tests. They successfully demonstrated that the watch, altimeter and compass all continue working even at minus 20 degrees centigrade. This is a professional sports watch you can rely on even in harsh cold conditions.

Depth meter

In 1985 Citizen introduced the world’s first diver’s watch with a depth meter using an electronic sensor. The Citizen Promaster Divers watch depth meter has only continued to evolve ever since. The water pressure sensor (at the 3 o’clock position on the case) only needs to be in contact with water for two seconds before it automatically starts measuring water depth to a maximum of 70 metres. It is also possible to display the time while displaying current depth and maximum depth. By eliminating the hassle of switching between modes Citizen have enabled divers to have both hands free at all times during dives.

 Eco-Drive and an altimeter and a depth meter?

Eco-Drive features an ultra-low power microcomputer that controls the depth meter and the altimeter. Activate either of them and the microcomputer analyses the information from the sensor, converts it into depth or altitude data and then rotates the hands to communicate the relevant information to the wearer. In addition the microcomputer controls the watch and checks the battery voltage, the amount of energy being generated, and the temperature. While Citizen deliberately use a CPU with a low clock speed, the real reason it can perform so many processes simultaneously is because of the expertise Citizen has developed in reducing Eco-Drive’s power consumption over the years.