Battery Condition Test
1.
Set the power switch to the OFF position.
2.
Connect the 80T-150U to the DMM.
3.
Set the DMM to the 200 or 400 mV dc range.
4.
Read the battery test voltage on the DMM or test instrument.
For DMMs with 10 M
Ω
input impedance, a minimum reading
of 100 mV is acceptable. For test instruments with 1 M
Ω
input
impedances, such as ScopeMeter®, a minimum reading of 75
mV is acceptable, With these minimum readings,
approximately 100 hours of battery life remain.
Battery Replacement
Warning
To avoid electrical shock, remove the probe from
the measurement surface before opening the case.
Totally reassemble the instrument before
attempting to use it.
1.
Set the power switch to the OFF position.
2.
Disconnect the 80T-150U from the DMM.
3.
Turn the 80T-150U so the power switch is facing down.
Remove the single screw located between the banana plugs.
4.
Grasp one case half in each hand. Pull the two halves apart,
beginning at the end with the banana plugs.
5.
Remove and replace the battery.
6.
Reassemble the 80T-150U as follows. Mate the two case
halves at the end where the cable enters the case, then
"hinge" the two halves together. Replace the case screw,
being careful not to pinch the probe cable or battery wires.
U1
F3.eps
Figure 3. Simplified Circuit Diagram
Performance Test
Complete the calibration procedure without opening the
temperature-to-voltage converter assembly and without making
any calibration adjustments. Observe the readings given in
[brackets]. Other readings are for calibration only.
Calibration
The calibration cycle of one year is recommended to maintain the
unit within the specifications given earlier. The equipment required
for calibration is listed in the table following the calibration
procedure.
Note
Values given in brackets apply to the Performance
Test.
Perform the following steps to calibrate the 80T-150U:
1.
Access the interior of the temperature-to-voltage converter by
removing the bottom case screw and separating the case
halves.
2.
Connect the 80T-150U to a DVM with 10
µ
V resolution, and
select mV dc range.
3.
Select the
°
C position of the switch. Immerse the probe tip 2
inches into a mercury thermometer monitored 0
°
C bath, and
allow 60 seconds for the readings to stabilize.
4.
Adjust R3 (see Figure 4) to obtain the following reading:
0.00
±
0.05 mV dc [0
±
0.2 mV dc]
5.
Select the
°
F position of the switch, and adjust R2 to obtain
the following reading:
32.0
±
0.1 mV dc [32.0
±
0.4 mV dc]
6.
Select the
°
C position, and move the probe tip to a 70
°
C to
90
°
C bath and again allow the readings to stabilize.
7.
Adjust R4 to obtain a DVM reading that agrees with the bath
temperature (BT) as monitored by a mercury thermometer.
°
C BT
±
0.05 mV dc [BT
±
0.2 mV dc]
8.
Select the
°
F position, and verify that the output is within
±
4
mV dc of the bath thermometer reading. If necessary, change
the DVM range to obtain an on-scale reading.
9.
Return the probe tip to the 0
°
C bath and check the output. If
readjustment is necessary, repeat steps 4 through 8 until
readings can be obtained without adjustment.
10. Set the 80T-150U switch to the OFF position, and remove the
80T-150U from the DVM.
11. Reassemble the 80T-150U.
12. The 80T-150U is now calibrated.
Probe Replacement
A probe kit (80T-150-7001K, PN 431023) is available for replacing
damaged or defective probes. The kit includes a probe and cable
assembly and an installation and calibration instruction sheet.
List Of Replaceable Parts
A schematic of the 80T-150U is shown in Figure 4. A list of
replaceable parts is shown in Figure 5. When ordering parts,
provide the description, Fluke part number, and the quantity
required.
Test Equipment Requirements
Instrument Type
Minimum Use Specifications
Recommended Model
Mercury Thermometer
0.1
°
C Resolution
Princo Model SAMA-CP45
Dewar Flask and Cap
1-Pint Capacity (for Ice Bath)
Thermos Bottle
Metal or Glass Container
1-Pint Capacity
Suitable for Boiling Water
Digital Voltmeter
100 mV Range with 10
µ
V Resolution
1000 mV Range with 100
µ
V
Fluke Model 8840A
For application or operation assistance or information on Fluke products, call:
800-44-FLUKE (800-443-5853) in U.S.A. and Canada, 31 40 267-8200 in Europe, 206-356-5500 from other countries
Fluke Corporation
Fluke Europe B.V.
P.O. Box 9090
P.O. Box 1186
Everett WA 98206-9090
5602 B.D. Eindhoven
USA
The Netherlands
