Fluke 5020A - Manual (Page 33)

General Operation
Introduction
4
4-3
Introduction
This section explains basic operation of the thermo-hygrometer. Detailed operation of the
thermo-hygrometer is explained in Chapters 5 and 6. Chapter 5 explains the menu
structure and the functions available in the menu structure and Chapter 6 explains the
communications interface for operating the thermo-hygrometer remotely.
DC Power Source
The thermo-hygrometer requires 12V DC to operate. The AC adapter is provided to
produce the DC power from an AC mains supply.
Caution
For CE compliance and for proper performance, use only the
AC adapter shipped with the instrument. If the AC adapter
needs to be replaced, contact an Authorized Service Center.
The AC adapter has circuits with high voltages inside that could
present danger of electric shock or fire if exposed. If the AC
adapter is damaged in any way or becomes hot, discontinue
use immediately, disconnect the adapter from any AC supply,
and replace the adapter. Do not attempt to open, repair, or
continue using a damaged or defective AC adapter.
The DC output from the AC adapter plugs into the 12 V DC power input on the left side
of the instrument (see Figure 3-3).
Battery
The thermo-hygrometer uses a 9V battery to maintain continuous measurement and
recording during power outages. The recommended battery type is a standard 9V alkaline
battery (NEDA 1604A or IEC 6LR61). During a power outage, or when the AC adapter
is disconnected, the display will be inoperable but measuring will continue if the 9V
battery is installed. If the alarm is enabled, the beeper will sound periodically to alert the
user of the loss of external power. With a fresh alkaline battery, measuring will continue
during a power outage for typically about 16 hours. During normal operation, the battery
charge is regularly checked, and if the low battery alarm is enabled, the user will be
alerted when the battery charge drops below approximately 50%. The battery charge
level can be viewed with a display layout that includes a stat type zone with one of the
fields set to BATT. To prevent inadvertent battery drain, remember to switch the power
switch off when external power is disconnected and the thermo-hygrometer is not in use.
To install or replace the battery, follow these steps:
1. Switch the power off and unplug the DC power cord.
2. Turn the thermo-hygrometer over to access the rear battery compartment. Press
down slightly on the battery cover and slide it out to remove it.
3. Remove the old battery if one is in place by lifting it up at the bottom and pulling
it out.
4. Slide the new battery in at an angle, observing the proper polarity so the
terminals mate correctly, then press the bottom of the battery down into the
holder.
5. Replace the battery cover.
6. Replace the DC power cord and switch the power on.