LAUREL LAUREATE LW20201SG1, Owner'S Manual

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Custom ASCII Protocol
A simplified, short protocol for use with these panel meters. It allows 31 digital
addresses. Not an industry-standard protocol, like the more complex Modbus
protocol , which is also offered with the meters.
Display Blank A rear panel input which blanks the display when the input is tied to logic
ground by a switch or 0V is applied (logic level true). The meter display will light
when the input is open or is held at +5V (logic level false).
Dribble A settable scale meter parameter in counts
which allows a flow to be shut off before the
setpoint value has been reached. For exam-
ple, set the setpoint to 100.0 (1000 counts)
and the dribble factor to -50 counts to turn off
the fill of a 100.0 lb bag at 95.0 lbs if the shut-
off system is known to dribble another 5.0 lbs
following shut-off.
Full Scale The maximum input signal range for which
the meter has been configured. For example,
the most sensitive full scale for the load cell meter is ±20 mV (signal range from
-20 mV to +20 mV).
Function Reset
A rear panel control input which resets Peak, Valley and any latched alarms
when the input is tied to logic ground by a switch or 0V is applied (logic level
true). To reset the value again, the input must be open or 5V applied (logic
level false) and then set low.
Ground Loop A closed conductive path in external ground wiring that allows stray currents to
flow in ground wiring, creating ground noise. The meters in this manual
minimize ground loop problems by mutually isolating the grounds associated
with meter power, signal input, and all output and communication options.
Jumper A push-on component which provides a short between two adjacent posts on a
circuit board. For example, jumpers are used to configure signal conditioner
boards for different signal types and full-scale ranges. Unused jumpers are
stored by pushing one side over an unused post.
Hysteresis Band
A band which controls relay action symmetrically around a setpoint. The relay
closes (or opens) when the reading goes above the setpoint plus one hyste-
resis limit, and opens (or closes) when the reading falls below the setpoint less
one hysteresis limit. A narrow hysteresis band is often used to minimize relay
chatter around a setpoint due to electrical noise or signal feedback caused by
load switching. A wide hysteresis band can be used for control applications,
such as turning on a fill pump when the tank level has reached a lower limit and
shutting off the pump when the tank level has reached an upper limit. The
hysteresis band will be equal to two hysteresis limits.