Transcript RA1: Relative Humidity (green wire)

PICNIC Demo Module 1
IP-based Psychrometer
陳育瑋、方煒
台大生機系
Objective
Development of a demo module
1. providing calculation of psychrometric
properties (thermodynamic properties of
moist air) based on dry bulb temperature
and relative humidity data measured.
2. teaching usage of PICNIC.
3. teaching VB programming.
Software
• Written in Visual Basic v6 (Microsoft, USA)
• Required PICOCX.ocx (Active X 控制項)
Device
Wiring
Two options for connection
 PC to Hub then to PICNIC: network cable
 PC to PICNIC: connecting cable
1
White-green
White-orange
1
2
Green
Orange
2
3
White-orange
White-green
3
4
Blue
Blue
4
5
White-blue
White-blue
5
6
Orange
Green
6
7
White-brown
White-brown
7
8
Brown
Brown
8
Network cable
Connecting cable
RHU300M T/RH
Sensor
Air Inlet and sensing part of
the sensor
Air outlet and Fan
RA0: Temperature
(yellow wire)
RA1: Relative
Humidity (green wire)
5 V output (red and black
wire from sensor)
Analog and digital I/O
Terminal connection of RHU-300
Terminal Content
1
Power source 5 VDC
2
Humidity Output (0~3 VDC)
3
GND
4
Temperature Output 50 k @25 oC
Your computer’s IP
Your PICNIC’s IP
Your computer and
PICNIC must be in
the same domain
(the first 3 numbers
should be the same)
when PICNIC is
directly connect to
the local PC.
PICNIC’s default IP: 192.168.0.200
Default IP
Default Gate Way
Port for Internet connection
Port for direct connection to PC
RHU-300M (5 Volt range)???
Sensor: thermistor 503
10 k resistor was used
Y
X
T = f(V) (10 k resistor was used)
70
2
y = -8.0347x + 49.5x - 11.598
2
R = 0.9961
60
50
t
40
30
20
10
0
0
0.5
1
1.5
v
2
2.5
Sensor: thermistor 503
4.7 k resistor was used
T=f(V) (4.7 k resistor was used)
rh
RH (3 Volt range)
100
y = 33.59x - 0.9079
80
R2 = 0.9999
60
40
20
0
0
0.5
1
1.5
v
2
2.5
3
Thermodynamic properties derived based
on given atmospheric pressure, dry bulb
temperature and relative humidity
A bug
Ver.1, 2007/7/27
A PsyChart software
previously developed
This is the VPD
This is the VPD’
Ver.2, 2007/8/2
PICNIC is connected to an actual
IP in the internal. In the same
domain with your PC IS NOT
required.
140.94.2.2
140.94.2.2
Press Start icon to read T and RH sensor data and
saved to a default mdb file.
Ver.2, 2007/8/2
140.94.2.2
Press Stop icon to terminate sensor data reading,
and export saved data to an excel xls file, with the
default file name, as shown in the next page.
Ver.2, 2007/8/2
Lack of date and time information.
Ver.2, 2007/8/2