Operation

The FBT-6 is connected to the network using the clip-on probes at the

end of the cable. The red probe is connected to the fieldbus + wire,

the black probe to the – wire and the green probe to the shield wire.

The + and – test leads are polarity sensitive and the Monitor will not

operate if they are reversed.

When first connected to a fieldbus, a version number is displayed

for several seconds. The Monitor then performs an Overall Network

Check to give the user a quick indication of network health.

The “FUNCTION” and “SELECT” buttons are used to select from

network parameters that can be examined with the Monitor. When

a function is selected, the data portion of the LCD display is blank

until the Monitor has collected and processed the data. After that,

the measured value is shown. The indication “OK” is shown if the

measured value is within the acceptable range. The indication “BAD”

is shown if the measured value is outside of the acceptable range.

The rotating symbol in the lower right corner of the display indicates

that there is network activity. A horizontal bar (underscore) under the

rotating symbol indicates that a frame was detected, but could not be

decoded. This is not a maintained function, so if a single “bad” frame

is detected, the underscore will only display for a short time. Periodic

“bad” frames will cause the underscore to blink.

Here follows a more detailed explanation of each of the Monitor’s

functions.