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2 other peripherals, 1 tims, Figure 34: relay driver circuit with relay – Campbell Scientific CR200/CR200X-series Dataloggers User Manual

Page 63: Figure 35: power switching without relay

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Section 5. Measurement and Control Peripherals

In other applications it may be desirable to simply switch power to a device

without going through a relay.

FIGURE. Power Switching without Relay

(p. 51)

illustrates a circuit for switching external power to a device without using a

relay. If the peripheral to be powered draws in excess of 75 mA at room

temperature (limit of the 2N2907A medium power transistor), the use of a relay

is required.

Figure 34: Relay Driver Circuit with Relay

Figure 35: Power Switching without Relay

5.2 Other Peripherals

5.2.1 TIMs

Terminal Input Modules (TIMs) are devices that provide simple measurement

support circuits in a convenient package. TIMs include voltage dividers for

cutting the output voltage of sensors to voltage levels compatible with the

CR200(X), modules for completion of resistive bridges, and shunt modules for

measurement of analog current sensors.

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