Laurel Electronics LAUREATE SERIES 2 DIGITAL PANEL METER - Manual (Page 26)

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can be set for direct readout in (milli)volts or (milli)amperes. Decimal point selection does not
affect the counts. For example, a 20V input may be displayed as 20.000V or 20000 mV.
The 5A range, designed for use with a 5A current transformer (CT), is scaled to produce 5000
counts with a scale factor of 1 and an offset of 0. Use with a specific CT will require the scale
factor to be set. For example, for an 800A input, 5A output CT, set a scale factor of 1.6. This is
the desired 8000 count display at 5A divided by the default 5000 count display at 5A. Then set
the decimal point to display to 800.0 at 5A.
All scaling methods applicable to DC, process, strain and load cell meters are available with
AC RMS meters.
INTERNAL SHIELD
To reduce noise pickup inside the meter or transmitter, the
RMS board is fitted with a flexible plug-on shield. If necessary,
This shield may be removed for jumper setting, but must be
reinstalled before closing the instrument.
SIGNAL SHIELDING
Signal Source
RMS
Board
Sig High
Sig Low
Earth Ground
Shield around twisted pair
Shielding for noise reduction
AC RMS measurements are susceptible to signal noise. This is especially true when the instru-
ment has a wide bandwidth. To minimize noise pickup, the input signal wiring should utilize a
shielded twisted pair, and the shield should be connected to signal low at the meter, as
illustrated. If signal low is close to earth ground, such as within 2V, signal low can further be
connected to earth ground at the meter, as illustrated.