•Stem conduction error.The problem may be that the actual temperature
of the sensor is not what you expect. This is often the result of stem con-
duction where heat flowing through the stem of the probe to ambient af-
fects the temperature of the probe. It is very important that immersion
probes be inserted to an adequately depth into the material being mea-
sured. Measuring temperature using a surface sensor can be especially
difficult as the sensor is directly exposed to ambient.
ErrorMessage at Power Up
The 1502A reportsan error during the power up self-test.
On powerup the 1502A performs a self-test of several of its key components.
A failureof a component will cause an error message to be displayed such as
“Err 4”. The possible error messages and theirmeanings are as follows:
Err 1Static RAM failure.
Err 2Nonvolatile RAM failure.
Err 3Internal data structure error.
Err 4ADC initialization failure.
Err 5ADC operation error.
Generally,each of these conditions require a qualified factory technician to re-
place a faultycomponent. Contact the factory for assistance. One possible ex-
ception mightbe if a large static discharge nearby disturbs the circuits. Cycling
the poweroff and back on again may allow the 1502A to resume normal opera-
tion.Another might be if the AC source voltage is incorrect, e.g. using 115 V
when the 1502A isconfigured for 230 V. Check the source voltage and the
1502A’sconfiguration and make sure they agree.
10.1 CE Comments

10.1.1 EMC Directive

FlukeCorporation, Hart Scientific Division’s equipment has been tested to
meet the European Electromagnetic Compatibility Directive (EMC Directive,
89/336/EEC).The Declaration of Conformity for your instrument lists the spe-
cificstandards to which the unit was tested.
The instrumentwas designed specifically as a test and measuring device. Com-
plianceto the EMC directive is through IEC 61326-1 Electrical equipment for
measurement,control and laboratory use – EMC requirements (1998).
As noted inthe IEC 61326-1, the instrument can have varying configurations.
The instrumentwas tested in a typical configuration with shielded, grounded
probe and RS-232 cables.Emissions may, in non-typical applications, exceed
the levelsrequired by the standard. It is not practical to test all configurations,
as the manufacturerhas no control over the probes the user may connect to the
instrument.
1502A Thermometer Readout
User’s Guide
40