Additel 221A Multifunction Temperature Calibrator User Manual - Manual (Page 74)

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11. HART Communication (only HART is available)
11.1 Brief and note
Thecalibrator is a secondary master device, and has no impact on the normal communication between a primary
master device and a HART device. The jacks of HART (refer to Table7‐1) have a built‐in HART resistor. This HART resistor
is optional and its rate current is 44mA.
Note 1: The calibrator can measure current only with a range of ‐30 to 30mA. If loop current (CA) is unnecessary, you
can bypass the current measure jacks, also , the calibrator can poll over 15 devices (address 1 to 15) with an external
HART resistor.
Note 2: The HART jacks can endure ±50V when an external HART resistor is being used.
In the calibrator HART mode, the calibrator will supply these operations as follows:
 SupportsHART process variables updating. The calibrator can show primary variable (PV), rang (%), PV current
value (AO), loop current (CA), thesecondary variable, the third variable, and the fourth variable. Thesecondary
variable, the third variable, and the fourth variable are special process variables definedby a transmitter.
 Support HART diagnostic and service: HART diagnostic and service operations will allow you to calibratea
supported HART instrument.
 Support HART setup: HART setupoperations allow you to configure common parameters of a supported HART
instrument.