Extech Instruments RH520A User Manual

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Alarm Conditions and the Alarm History
When in Standard View mode:
 If the ALARM display icon is flashing – an Alarm condition currently exists.
 If the ALARM display icon is ON steady – there are past Alarms to view in the Alarm history.
Use the ALARM button to view the Alarm history as described elsewhere in this manual.
 If an Alarm is tripped, press the ALARM button to silence it.
 Press and hold the SET button for 2 seconds to clear an alarm through the external relay
module.
When in Alarm View or Time View mode:
 If the ALARM display icon is flashing – the cursor is currently on an Alarm condition.
 If the ALARM display icon is ON steady – there are past Alarms to view in the Alarm history.
Use the cursors or the ALARM button to view the Alarm history as described elsewhere in this
manual.
Note that the Alarm display icon and the external alarm relay module can be controlled
separately as indicated in the statements above.
Battery Replacement
The 5-segment battery life indicator allows the user to track the status of the battery. When all
5-segments are dark, the battery is fully charged. Segments switch off as the battery ages. When
the battery indicator has only one segment left the batteries must be replaced immediately.
1. Open the battery compartment on the rear of the instrument
2. Remove the old batteries and replace with three (3) heavy duty alkaline ‘AA’ batteries
observing polarity
3. Replace the battery compartment cover securely
4. The RH520A will require a “Programming Reset” to reset the display. Press the RESET
button located inside the battery compartment. “Reset” clears all settings. Time, Date
and the logging interval need to be entered. The measurement data and alarm history,
however, will still be retained in the non-volatile memory.
You, as the end user, are legally bound (Battery ordinance) to return all used batteries
and accumulators; disposal in the household garbage is prohibited!
You can hand over your used batteries / accumulators, gratuitously, at the collection
points in our branches in your community or wherever batteries / accumulators are sold!
Disposal
Follow the valid legal stipulations in respect of the disposal of the device at the end of its
lifecycle

Extech Instruments RH520A Specifications

Temperature and Humidity

temperature range	-28 to 60 °C
temperature accuracy	±1.0 °C
humidity range	10 to 95 %
humidity accuracy	±3.0 % RH
dew point temperature	-28 to 60 °C

Power

power supply	Three ‘AA’ batteries and AC adaptor
dc voltage	5 V
battery life	4 weeks typical

Operating Environment

operating temperature range (control module and display)	0 to 50 °C
operating temperature range (sensor)	-28 to 60 °C
operating humidity (control module and display)	90 % RH max.

Memory and Data Logging

internal memory storage	49, 152 complete reading sets
sampling interval	0.1 to 199.9 minutes
alarm output current	3.4 mA @ 5 VDC

Weight and Dimensions

weight	357 g
dimensions	127 x 196 x 23 mm