Campbell Scientific SDM-IO16 16-Channel Input/Output Expansion Module - Manual (Page 13)

SDM-IO16 16 Channel Input/Output Expansion Module
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 should be as short as possible and
typically should not exceed 6 m. For CRBasic dataloggers,
longer cable lengths may be possible if the SDMSpeed
instruction is used (see Section 6.2.3). Too long of cable length
will adversely affect communication performance between the
module and datalogger. NOTE
4.1 Terminal Connections
The SDM-IO16 uses spring-loaded terminal blocks, which provide quick,
vibration resistant, connections. The output terminals are labeled 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. NOTE
Strip insulation
and insert wire
Address switch
location
FIGURE 4. Use of Terminal Blocks
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