Pneumatic counters, logic controllers and timers are used in place of electrical equipment in environments where electricity is unavailable or can't be used. These pneumatics systems are incredibly accurate and can be used in other environments too, especially when the device must continue working even in the case of an electrical shortage. RS Components works with leading manufacturers like SMC, Parker and Norgren to make sure our range is the best around.
Pneumatic counters work within specified pressure ranges to count and tally pulses of compressed air, which are then translated numerically and shown on a mechanical digital display. There are two types of pneumatic counters: totalising counters and pre-set counters. Totalising counters tally each pulse of air to display the total number of pulses during a certain time frame, whereas pre-set counters monitor and control operational sequences and display them in numerical form. Totalising counters are used for production counting or for the recording of flow volumes and pre-set counters are found in high-speed consumable goods industries where operational sequences like filling, capping and labelling occur.
Logic controllers are used in the control of industrial processes to execute specific actions. These actions can be performed by AND units, OR units, booster units and timers. Pneumatic logic controllers perform similar functions to relays, pneumatic timers switches and counters, but utilise compressed air as the controlling mediums instead of electrical currents. Pneumatic logic controllers are useful in environments exposed to dust or moisture, because they operate using compressed air and not electrical currents.
Pneumatic timers are used in industrial systems for the precise control of air input signals. Most pneumatic timers use a chamber and a piston to measure time, however, other mechanisms can be used, including spring diaphragm and volume fill technology. Pneumatic timers are used where an electrical current is undesirable, restricted, unavailable or dangerous, such as in the mining, oil and gas industries. They can be used where precise time control is important. By utilising a piston and control valve rather than an electrical current found in a standard timer, such as plug-in time switches, pneumatic timers do not generate sparks that could cause fires or explosions.
Dave takes a look at switch testing at APEM for IP and IK rated switches.