Midas

The Detector Doesn’t Have to Be Where the Gas Is

This is the whole idea, and it’s worth spelling out, because the consequences run through everything else.

A conventional fixed detector sits at the point being monitored. In a semiconductor fab, that means inside a cleanroom, inside a gas cabinet or in a subfab space. So routine service becomes a gowning procedure, a permit, or a shutdown of the tool it’s protecting.

Midas is extractive. It draws a sample through a line, from the local area or a remote point up to 30 metres away, to a sensor cartridge inside its own chassis. So the detector mounts somewhere a technician can reach it in ordinary clothes. Calibration, cartridge changes and fault finding all happen there, rather than at the sample point.

On a fab with dozens of monitored points, that changes the maintenance economics, not just the detection.

Why the Flow Matters

A remote sample is only as good as the certainty that it arrived.

Draw a sample down 30 metres of line, and several things can go wrong quietly. Flow can drop as a filter loads, a line can partly block, or a fitting can leak and dilute the sample with room air. In each case, the cartridge still reads, but it reads low. That’s wrong in the unsafe direction, because a real leak can look like a small one.

Midas monitors the sample flow, so a problem with the sample line shows up as a fault rather than a quiet under reading. On the Midas-M, an optional Line Integrity Test module goes further, detecting a leak in the tubing itself.

The Cartridge Is the Product

Whichever model is specified, what it detects is a cartridge decision.

The Midas-M offers more than 30 gases, covering toxic, flammable and oxygen sensor cartridges, for gases used or generated in semiconductor and other manufacturing. That range reflects semiconductor process gases, rather than general industrial ones, which is why Midas turns up where arsine, phosphine, silane, diborane, hydrogen fluoride and tungsten hexafluoride are in use.

Cartridges are plug and play, and pre-calibrated at the factory, so they’re ready when you are. That means quick replacement, and no operator error from an incorrect or depleted sensor. Each smart cartridge carries an onboard e-calibration certificate, so the detector knows what’s fitted and when it was calibrated, without anyone writing it down.

The Reflex sensor health check adds a further safety check on the sensor, and event logging lets you review sensor history.

The Midas Range

The Midas-M is Honeywell’s current platform. It’s a fixed extractive single point detector with a 4-in-1 multi smart sensor cartridge, built for a smaller footprint and lower cost of ownership. It comes in four parts: the main module, the mounting bracket assembly, the sensor cartridge and the pump module.

The Pyrolyzer is a different kind of addition. Nitrogen trifluoride and the perfluorinated compounds are chemically stable, which is exactly why they’re used, and stable compounds don’t react readily with a sensor. A pyrolyzer thermally breaks them down into products a cartridge can detect, which is the same principle as the Gastec Pyrotec on the detector tube side.

Talk to our Technical Consultants about which model and cartridges suit your gases.

Integration

Three Form C relays are built in, for alarm one, alarm two and fault, so the detector can drive a local response directly, rather than only reporting to a panel. An optional external relay module adds nine more, and an optional Alarm Verifier module helps reduce false alarms.

The Midas-M also has an isolated 0 to 21 mA analogue output with fault and event reporting, Modbus TCP over Ethernet, and Power over Ethernet. So a single Ethernet connection can carry power, control and communication. On a fab with a site wide monitoring platform, that’s the practical connection.

At the detector, a large LCD with a multicolour backlight, bright LEDs and intuitive icons show readings and alarm state at a glance. Menus are password protected, and a remote web browser interface allows set up and service from a PC.

Built to Be Serviced

Construction is modular, with the front, the pump, the sensor cartridge, the main board and the base all separate.

That matters on a platform expected to run for years in a facility where downtime is expensive. A failed pump is a pump replacement, not a detector replacement, and the same applies across the modules. The extractive pump is rated for a 2 year life, and the Midas-M cartridges carry a 2 year warranty.

TempraSure temperature compensation and full CE immunity to radio frequency interference help keep readings stable in a busy fab.

Where It’s Used

Semiconductor fabrication and subfab. Gas cabinets, valve manifold boxes and bulk gas delivery. Compound semiconductor and photovoltaic manufacturing. Light industrial manufacturing using specialty gases. University and research laboratories. Aerospace. Wastewater. Any facility where the monitored point is difficult or expensive to access.

Gases

More than 30 gases are available across the Midas-M cartridge range, grouped by category.