Trolex XD One Alarms

Modified on Tue, 13 Feb at 11:31 AM

The Trolex XD One uses two LED indicators alongside audio sequences to alert users to an alarm threshold being breached for STEL and TWA.

STEL - Short-term exposure limit alarm (Indicator 1)

- The XD One will flash the amber STEL indicator alongside an audible alarm (2 beeps per second).

- The XD One is factory programmed with the following default STEL threshold:

- 1,000 μm/m3 over 15 minutes

- The XD One uses the following calculation for the monitoring of STEL threshold breach (STEL time in minutes):

TWA - Time-Weighted Average alarm (Indicator 2)
- The XD One will flash the red TWA indicator alongside an audible alarm (3 beeps per second).

- In the event that both alarms are triggered simultaneously, the TWA alarm will take priority.

- The XD One is factory programmed with the following default TWA threshold:

- 1,000 μm/m3 over 8 hours

- The XD One uses the following calculation for the monitoring of TWA threshold breach (TWA time in minutes):

The default threshold limits have been defined based on a quarter of the permissible limit for most respirable dusts as outlined in the EH40/2005 guidelines.

Advice outlined in EH40/2005 states that where no specific short-term exposure limit is listed, a figure three times that of long-term exposure limit should be used. However, always refer to local guidelines and legislation to ensure that alarm warning thresholds are set at appropriate and permissible values for the intended operating environment.

Note: The XD One is a personal safety device and it is the operator’s responsibility to respond accordingly to any warnings, alarms or alerts in accordance with site regulations and instructions. Follow all warnings and instructions marked on the instrument.

Alarm Acknowledgement

In the event that a warning alarm is triggered, the XD One will auto-latch to ensure that
a conscious action is made to acknowledge the warning. During alarm state, users can acknowledge triggered alarms which will silence the audio alarm; however, the LED warning indication will remain illuminated (solid) to indicate the alarm conditions are still present.

At the point of particulate levels decreasing below the permissible threshold (95%) of the alarm set point, the alarm will reset and the illuminated LED will switch off.

To acknowledge a latched alarm, press and hold the power button for 2 seconds then release after which the XD One will confirm with an LED sequence: scrolling illumination of alarm colour, followed by a scrolling green sequence.

Note: If an alarm is not acknowledged by the user, the XD One will remain latched with the illuminated LED and audio warning indefinitely.

The XD One device will only re-alarm on increasing or continued particulate levels above the permissible threshold, after the original alarm has been user acknowledged and self-cleared.