SDM-SW8A Switch Closure Input Module
1. Function
The 8 channel SDM-SW8A Switch Closure Input Module (see Figure 1) measures up to 8 channels of switch closure or voltage pulse inputs. Each channel may be configured to read single-pole double-throw (SPDT) switch closure, single-pole single-throw (SPST) switch closure, or voltage pulse. Output options include counts, duty cycle, and state.
The SW8A is addressed by the datalogger, allowing multiple SW8As to be connected to one datalogger (refer to Theory of Operation, Section 9). Sixteen addresses are available, but for most applications, Campbell Scientific, Inc. recommends no more than 4 SW8As be connected to one datalogger. If more SW8As are required, please consult Campbell Scientific's Marketing Department.
In October, 1988, the SDM-SW8A was introduced. Edlog Instruction 102 is used for communication with the SW8A. CRBasic dataloggers use the SDMSW8A instruction. Previous to October, 1988, the SDM-SW8 (no "A") was offered for use only with the CR10, utilizing CR10 I/O Instruction 15.
SDM-SW8As are not compatible with CR10s containing Instruction 15, and SDM-SW8s are not compatible with CR10s containing Instruction
102.Contact Campbell Scientific's Marketing Department for update options if incompatibilities exist.
FIGURE 1. SDM-SW8A Front Panel