Low Battery Condition; Wet Bulb Temperature Readings; Psychrometric Chart - Wavetek Meterman TRH22 Mode D'emploi

Low Battery Condition

N
When the battery voltage is under proper operation requirement, the
symbol displays on the LCD and the battery needs to be replaced.

Wet Bulb Temperature Readings

Occasionally the Wet Bulb temperature is required. Use the following
procedure and your TRH22 to obtain the wet bulb temperature.
1. Determine RH% condition with the TRH22.
2. Determine temperature (dry-bulb) with the TRH22.
3. Locate dry bulb (DB) temperature line on the Psychrometric chart
(vertical line across the bottom of the chart).
4. Locate relative humidity (RH) line on the chart (curved line across
the chart).
5. Find the intersection of the DB and RH lines on the chart.
6. Draw a diagonal line, starting at your intersectioin point, until the
Wet Bulb (WB) point is determined. (The wet bulb temperature line
is at the outmost curve of the chart).
For example, locate the DB temperature of 78°F on the Psychrometer
chart. Locate the RH conditions of 50% RH on the chart. Draw a
diagonal line up to the 65° F WB point.

Psychrometric Chart

50
40
40 50
80
70
60
60 70
DRY BULB TEMPERATURE (F)
90
80
90
100
5
.028
.024
.020
.016
.012
.008
.004
120