Hydrological Services Pty Ltd
Data Logger Model ML1-420
©
Copyright
ML1-420 100-5
Issue 1.00 6 Apr, 2011
3. Installation
The MiniLog has a single DB9 female connector, which is mainly used for communications –
(the digital input and external power may be taken through this connector, making it pin
compatible with the ML1). The pinout is designed to be compatible with direct connection to
a PC Comm port. Note that when external power is supplied, whether though an external 12V
battery or RS232 handshake lines, the power drawn from the internal battery is reduced to
zero.
The digital input from the TBRG, external 12V power and the 4-20mA transducer are
connected to the internal screwless terminal blocks – these specific terminals are used
because they keep a constant tension on the wires that are inserted.
1. Use a small flat blade
screwdriver and push-
down on the orange
2. Insert the stripped
wire here.
3. Release the orange
lever to secure the wire.
4. Pull on the wire to
make sure it is secure.
TBRG
12V
Battery
WL3100
AD375MA
ML1-420
4-20mA
“OR”
Submersible
4-20mA
Pressure
Transducer
Model: PS98i
“ML1-420 Typical Application”
Rainfall
Water Level