18
Use with SunScan
BF5 User Manual v
2.
3
Use with SunScan
Setting up the BF5
The BF5 is simple to operate. Make sure the BF5 output units are set to
the PAR molar units (
mol m
-2
s
-1
) using
SunRead
.
As a general guide, the above-canopy reference measurements should be
made close to, or above, the position of the
SunScan
probe. Tall
canopies will undoubtedly exercise your ingenuity in achieving this!
Using the tripod
The BF5 has a camera tripod mounting screw socket in the base. This is
probably the most convenient mounting method to use above low field
canopies (up to about 1.8 m high). If you are working with canopies higher
than this, it may be convenient to use the cross arm mounting kit type
BF5-M
which is compatible with the Delta-T Weather Station mast, and
with many building scaffolding systems - or devise your own.
Levelling
The BF5 is equipped with a miniature bubble level. The tripod supplied
type
BFT1
has 3-axis adjustment to facilitate levelling. The sensor is level
when the bubble is within the central circle.
It is more important to level the BF5 accurately than the SunScan probe.
Connecting to SunScan
Options:
Use cable type
EXT/8w-
05
with optional extension cables type
EXT/8w-xx
(where x = 5, 10 or 25m) to connect the BF5 directly into
the socket on the back of the SunScan Probe.
Or use the
BF5-RL4
to
SS1-RL4
Sunscan radio link
If you are just checking to see that the BF5 is working, or measuring Leaf
Area Index, it is OK to use the radio link.
Place the SunScan next to the BF5
Run the
SunData
program on the PDA and press
Read
.
The Incident and Transmitted radiation readings should then appear
on the SunData display.
Check that the “Transmitted” (i.e. SunScan) and “Incident” (BF5)
readings are within 10% of each other.
(Note: 10% corresponds to a Leaf Area Index error of 0.1 – which is
normally an acceptable precision for LAI measurements)