The SCT has an integral 5-28VDC / DC to DC converter. The 4-20mA transmitter accepts 0-1 VDC full scale signal from your sensor convert it to a 4-20mA process signal. The unit is ideal for logic power 5V systems where 24V is not available. Its high efficiency DC-DC converter requires ~ 170mA when the output is 20mA and can drive loads up to 1k Ohms (including your wire resistance). Note: The unit provides no I/O isolation, so care must be taken when using A.C. signals (Options 31-33) and avoiding “ground loops (engineer’s nightmare). Use this unit for power input applications of 4-6VDC.
SCX Loop-Powered Signal Conditioner
The SCX is a loop powered signal comditioner. It supplies 5VDC at <3.5mA to the listed (SCV Series) signal conditioners (Digits 4 & 5) without affecting the 4-20mA accuracy. As a stand alone, the SCX accepts a 0-1VDC or 0-1mADC signal.
OTEK's SCV is the basic signal conditioner. It accepts 5VDC power input (see section 4.0 on page 3), current requirements vary from few microamps to under 3.8mA depending on model. Their output is 0-1VDC into a >100K Ohm load. No adjustments are included. The module is 0.9 x 0.9 x 0.25”.