Baker Hughes Masoneilan 12400 Series, Instruction Manual & Safety Manual

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® 2017 Baker Hughes, a GE company. All rights reserved. Masoneilan 12400 Series Transmitter/Controller Instruction Manual | 27
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Calibration of transmitter for level application:
The electronic circuit is calibrated towards two reference levels (REF L and REF H). See schematic below.
▪
REF L corresponds to the displacer completely out of liquid.
▪ REF H corresponds to the displacer fully immersed in the liquid of Specific Gravity used for calibration [SG CALIB].
The loop current corresponding to REF L may be set through [MA LO:mA] via [VAR SET]; it is generally 4mA.
The current corresponding to REF H may be set through [MA HI:mA] via [VAR SET]; it is generally 20mA.
The value of [MA HI:mA] must always be higher than the value of [MA LO:mA].
The level indication corresponding to REF L is set through function [LRV] via [VAR SET]; it is expressed in the unit set through [UNIT]
function; if UNIT is "%", [LRV] must be 0.00%.
The level indication corresponding to REF H is set through function [URV] via [VAR SET]; it is expressed in the unit set through
[UNIT] function; if UNIT is "%", [URV] must be 100.00%.