Honeywell SC1000 - Manual (Page 14)

page 14 008-0608-00
1.4 What is Signature Calibration ?
1.4.1 Overview
A small integrated circuit is located either inside the transducer, in an in-line package
between the instrument and the transducer, or in the connector of a cable. All data
necessary to set up the transducer with the instrument are stored (even linearity data),
and setup is automatic when a new transducer is connected to the instrument.
The Strain-Gage Input channel of the SC Series is designed to operate with Signature
Calibration. It will automatically set itself up with transducers which contain the mem-
ory device, but can also be set up using a front-panel interactive procedure. The Sig-
nature Calibration module can also be programmed from the instrument’s front panel.
Signature Calibration is only available with unamplified strain-gage transducers.
1.4.2 Benefits
The benefits are:
• The transducer’s Calibration Record is always located where it is needed most...
with the transducer.
• The instrument is always set up correctly with the transducer.
• Interchanging of transducers and instruments is a quick process.
• A User Calibration Data area that can be altered by customers to fit their require-
ments.
• A Factory Calibration Sheet Data area, unalterable by the customer, can be cop-
ied back into the User Calibration Data.
1.4.3 Information
Stored
The following information is stored inside transducers equipped with Signature Cali-
bration:
• Full-scale mV/V: The full-scale millivolt-per-volt (mV/V) rating of the transducer
when its full load is applied; also called “calibration factor”.
• Shunt-Cal mV/V: The millivolt-per-volt output of the transducer when the shunt
calibration resistor is placed across its (-)SIGNAL and (-)EXCITATION leads.
• Shunt Resistance: The resistance value, in Ohms, that was used to obtain the
shunt-cal mV/V value above.
• Full-Scale Value: The full scale value of the transducer, in engineering units.
• Engineering Units: The engineering units that the transducer is calibrated in (i.e.
pounds, grams, pascals, inches of water, etc.).
• Serial Number: The serial number of the transducer.
• Excitation Voltage: The magnitude and type of signal used to excite the trans-
ducer.
• Linearization Points (optional): These can be used by an instrument using Shunt
Calibration or Millivolt-per-Volt Calibration to correct any non-linearity in the trans-
ducer and thus improve the accuracy of the system. An additional “multiple-point
calibration” can be purchased with the transducer that allows linearity correction
information to be placed into its Signature Calibration module.