Murco MGS Spezifikationen PDF herunterladen (Seite 20)

MGS Installation and Operation Manual

20 1000-0085 Rev 0

Section 4. Operation and Stabilisation

On powering up, the MGS will sense for the presence of gas after an initial

warm-up delay of 5 minutes. The green LED will flash at 1 second intervals

during the warm-up.

In an alarm condition:

• green LED stays on and the red LED is on

• audible alarm operates (if not disabled and after delay, if set).

• relay output activates (after a delay, if set)

• V and I output changes proportionally with gas concentration.

In a fault condition:

• green LED will be off and the red LED will be on

• voltage/current fault output will activate:

o 2mA on the 4-20mA output

o 0.5V on the 1-5V output

o 1.0V on the 2-10V output.

The typical time for various sensor types to stabilise is shown below.

Sensor Type Stabilisation Time

Electrochemical (EC) 20-30 seconds

Semiconductor (SC) 1-3 minutes

Infrared (IR) 2 minutes

On power up, the electrochemical sensor outputs a signal voltage normally

below the set alarm level. Semiconductors output over the + max scale, i.e.,

> 5V. Both move towards zero as they stabilise.

If sensors have been in long-term storage or the detectors have been turned

off for a long period, stabilisation is much slower. However, within 1-2 hours

sensors should have dropped below the alarm level and be operational. You

can monitor progress exactly by monitoring the 0-10V output. When the

output settles around zero the sensor is stabilised. In exceptional

circumstances the process can take up to 24 hours or more.

1 2 ... 15 16 17 18 19 20 21 22 23 24 25 ... 30 31

Keine Kommentare

Murco MGS Spezifikationen Seite 20