Specifications, Power considerations – Campbell Scientific SDM-CD8S 8 Channel Solid State DC Control Module User Manual
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SDM-CD8S 8 Channel Solid State DC Control Module
The SDM-CD8S is a synchronously addressed datalogger peripheral.
Datalogger control ports 1, 2, and 3 are used to address the SDM-CD8S, then
clock out the desired state of each of the 8 control ports. Up to 15 SDM-
CD8Ss may be addressed, making it possible to control a maximum of 120
ports from the datalogger’s first three control ports. The SDMCD16AC
instruction is used to control the SDM-CD8S in CRBasic dataloggers. In
Edlog dataloggers that support SDM-CD16 devices, I/O Instruction 104 is
used (some old CR7s may use Instruction 29).
In addition to SDM control, the SDM-CD8S has the option of being operated
in a shift register mode. To operate in the shift register mode the address
switch is set to 15.
Ensure that the datalogger contains the appropriate instruction
and test your datalogger program before going in the field.
NOTE
2. Specifications
Compatible dataloggers:
CR9000(X), CR5000, CR3000,
CR1000, CR850, CR800, CR23X,
CR10(X), 21X, and CR7.
Supply voltage:
8 to 26 VDC
Logic current drain at 12 VDC:
15 mA quiescent;
2.5 mA per active LED (manual or
auto)
Maximum cable length:
20 ft total to all SDM devices.
Consult CSI if longer lengths are
necessary.
Toggle switch: MANUAL,
AUTO
Individual dip switches for manual
Maximum current per channel: 1
Amps
Maximum current all channels total: 6 Amps
Actuation/release times:
8
μs/200 μs
Operating temperature: -40
° to 70°C
Dimensions:
11.1 x 8.6 x 2.4 cm (4.4 x 3.4 x 0.9 in.)
3. Power Considerations
The SDM-CD8S power requirements may be large compared to most
Campbell Scientific products. For most applications, an external power supply
(see Figure 2) is recommended to power the SDM-CD8S.
For some applications, it may be convenient to use the datalogger supply to
power the SDM-CD8S (see Figure 2). For long-term applications, the lead
acid power supply available with our dataloggers should be used, allowing the
batteries to be float charged. It is not recommended that the datalogger
alkaline supply be used to power the SDM-CD8S for long-term applications.
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