10
MEMORY BACKUP
During battery replacement, the contents of user-programmed memory
(data, operating modes, etc.) can be saved. Prior to removing the old battery,
turn off the instrument, and connect a Model 80010 battery charger. Then
exchange batteries, and disconnect the battery charger. Do not leave the bat-
tery charger connected to instruments with non-rechargeable batteries.
OPERATION WITH RECHARGEABLE BATTERY
Model 80010 provides a 9-volt Ni-Cd battery and recharger suitable for use
with the unit. This battery provides 15 hours of continuous operation. This
duration can be extended indefinitely by operating simultaneously from both
the battery and recharger.
OPERATING INSTRUCTIONS
The following instructions make reference to keypad inputs, and display
readouts. Refer to Figure 2 to locate key switches, and identify display dif-
ferences between thermometer models. Model HH-22 is similar in layout to the
HH-23, except operation is limited to K and J thermocouples.

1. DIAGNOSTICS

Automatic diagnostics provide error indicators which are described below.
PROBLEM: LIKELYCAUSE:
Blank display, unit does not (1) Improper battery installation. Check
power-up. battery polarity.
(2) Dead battery.
Low BATAnnunciator. (1) Low battery voltage, install a new
battery. If problem persists, consult
factory.