Solar Panels
6
The SP10R and SP30R panels are supplied with shunt regulators suitable for 12V
lead-acid batteries. The connection is normally made at the battery terminals.
In contrast, the SP10 and SP30 are designed to connect to the terminals of the
battery charging circuit of the type fitted to the rechargeable CR200X, CR3000
and CR6 dataloggers and the CH/PS series power supplies. The SP30 can also be
used with these dataloggers and power supplies (see Section 3.3) in some
applications.
It is essential to ensure that the wires from the solar panel are
fixed to the structure of the tower or tripod. This is to prevent
the wire moving in the wind which can cause premature failure
of the system.
The SP60 and SP100 are usually supplied with a separate Morningstar regulator.
Please refer to the instructions supplied with that regulator for wiring and
configuration instructions.
3.1 Connecting the SP10R or SP30R
The SP10R are supplied with loose shunt regulators which have to be wired into
cables connecting the panel to the battery. The wires of the shunt regulators are
clearly identified. Connect the shunt regulator as shown in Figure 5.
Solar
Panel
Solar
Batt
+VE
+VE
-VE
12V
Battery
Lead-Acid
To
Datalogger
+
-
Shunt Regulator
+
-
Figure 5. Connection of Shunt Regulator for SP10R Panels
Observe the correct polarity when making connections to the
shunt regulator. Failure to do so may damage the regulator
beyond repair.
The shunt regulator operates by detecting the battery voltage on its output. When
this voltage reaches a defined limit (nominally 14.6V) the shunt regulator
effectively shorts out the solar panel preventing further charging. (A diode in the
regulator prevents reverse discharge from the battery.)
With the panel shorted out, the battery voltage slowly drops to a point when the
regulator re-enables the solar panel input. This results in cyclic on/off charging: as
the battery becomes charged the regulator shorts out the panel for a greater
proportion of the time.
Recent versions of the shunt regulator are fitted with a small green LED which
protrudes from the regulator case close to the point where the wires emerge. This
CAUTION
CAUTION