Terminal Connections - Campbell SDM-IO16 User Manual

SDM-IO16 16 Channel Input/Output Expansion Module
NOTE

4.1 Terminal Connections

NOTE
6
Multiple SDM-IO16s can be wired in parallel by connecting the datalogger
connections of one SDM-IO16 to the next.
The transient protection of the SDM-IO16 relies on a low resistance path to earth.
Ensure that the ground return wire has as low a resistance as possible. Where very
long cable runs are likely, or where lightning damage is a possibility, the SDM-
IO16 can be fitted with optional gas discharge tubes. Please contact Campbell
Scientific for details.
The total cable length connecting SDM-IO16s to SDM-IO16s and
the datalogger should not exceed 6 m. Total cable lengths in excess
of 6 m will adversely affect communication performance between
the module and datalogger.
The SDM-IO16 uses spring-loaded terminal blocks, which provide quick,
vibration resistant, connections. The output terminals are labelled 1 to 16. A
common ground connector is provided between each pair of terminals
Use a screwdriver in either the top or front slot, as appropriate, to open the
terminal spring. Strip any insulation from the wire to give 7 to 9 mm bare wire.
Push the wire into the opening, and, while holding it in position, withdraw the
screwdriver to release the spring. The wire will now be firmly held in place. See
Figure 4, below.
You cannot reliably insert more than one solid-core wire into one
terminal connector unless the wires are soldered or clamped
together. When inserting more than one stranded wire, twist the bare
ends together before insertion.
Figure 4. Use of Terminal Blocks
Address switch
location
Strip insulation
and insert wire