Table 2-47 Metric Units - Honeywell UMC800 Reference Manual

2.54 RH Function Block,

Table 2-47 Metric Units

Metric
DRY
WET
PRES
Usage Tip
It is physically impossible for the wet bulb to be warmer than the dry bulb. If this appears to be the case, it
implies a problem with the sensors, and will result in a RH greater than 100%. Downstream blocks should
detect that situation and react promptly.
Example
Figure 2-56 shows an RH function block example.
A setup parameter allows inputs to be in Degrees F or Degrees C. When Degrees F is selected, pressure is
assumed to be in PSIA. When Degrees C is selected, pressure is assumed to be in Pa. (101325 Pa = 1 std.
Atmosphere.
3/99
continued
ON OFF
°C °F
°C °F
Pa PSI
Figure 2-56 RH Function Block Example
Function Block Reference Guide
Function Blocks
167