Chapter 3 ________________________________________________________________  Installation 
 
VAISALA ________________________________________________________________________ 53 
You need to replace screw terminals 1 and 2 with the screw terminals 
delivered with the DXL421 modem. The DXL421 installation location is 
illustrated in Figure 29 on page 52. Use the wire set delivered with the 
modem when connecting the modem supply voltage lines and data lines. 
See the wiring instructions in Figure 29 on page 52. After the installation, 
turn on the AC (mains) switch and the battery backup switch, if you have 
installed it. 
 
NOTE 
If you need to reconfigure the DXL421 modem, use the jumper/dip switch 
settings on the DXL421 modem. The jumper/switch settings are printed 
on the left 
side of the modem. 
The available settings are:
 
 Originate or Answer 
 1200 baud or 300 baud 
 Speed buffer for 9600 baud On/Off 
 2-wire or 4-wire 
The default settings are:
 
 Answer 
 300 baud 
 Speed buffer for 9600 baud Off 
 2-wire