Input Calibration; Overview - Honeywell DR4500A Product Manual

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7.1 Overview

SHOCK HAZARD—WARNING!
Disregard of these instructions may cause injury or death.
INPUT CALIBRATION MAY REQUIRE ACCESS TO HAZARDOUS LIVE CIRCUITS, AND
SHOULD ONLY BE PERFORMED BY QUALIFIED SERVICE PERSONNEL. MORE THAN
ONE SWITCH MAY BE REQUIRED TO DE-ENERGIZE UNIT BEFORE CALIBRATION.
Introduction
This section describes the field calibration procedures for inputs 1 and 2. All DR4500A recorders are
factory calibrated prior to shipment. It should not, therefore, be necessary to recalibrate the recorder when it
is initially installed. However, you must recalibrate the input if any one of the conditions summarized
below applies:

The thermocouple or RTD input must meet published* accuracy rates. Note that the factory calibration
at reference is ±1.2°F plus ±10 microvolts for thermocouples or ±0.3 ohms for RTDs.
* Specifications 44-45-03-15

You are using a 0–10 Vdc input. Recalibration is necessary because the resistor network used for this
input has a tolerance of ±1.0%.

You have cause to believe that the recorder is out of calibration.

You must perform regularly scheduled or periodic recalibration based on your own needs.

You have performed specific servicing activities such as replacement of an input PCB.
ATTENTION
Replacing a main PCB does not normally require recalibration since a new main PCB is
already factory calibrated, whereas an input PCB is not.

You have changed the input type through configuration which results in the loss of the previous field
calibration, but restores factory calibration. See subsection 7.2 Restoring Factory Calibration paragraph
that follows.
Release K DR4500A Classic Series Circular Chart Recorder With or Without Control Product Manual
May 2013

7. Input Calibration

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