The WISCO Signal Isolator is a WISCO Industries product designed to
break the galvanic path between a transmitted signal source and a receiving
device, such as a controller or recorder. The Signal Isolator solves the problem of
transferred signal distortion due to ground potential differences. The Signal
Isolator is highly effective in eliminating unreliable or inaccurate signal transfer
by providing total current-to-current signal isolation. The Signal Isolator derives
its operating potential from the existing input loop current and, therefore, does
not require a dedicated power supply. The Signal Isolator is placed in series with
the drive signal and provides and output current that is proportional to the input
signal current.
When a signal isolation device is installed it is important to consider the
voltage drop or additional line resistance that will be placed in the system. Any
additional load tends to reduce the line or drive potential and may exceed the
source rating. The effect of voltage drop within the system must be calculated to
ensure that drive capability is not exceeded. The Signal Isolator features a
maximum fixed voltage drop of 2.5 VDC (4.2 V for 10 - 50 mA) which remains
constant over the entire temperature range of 0 ˚C to 50 ˚C