TPI A254 User manual

A254
User Guide

CONTROLS AND FUNCTIONSSAFETY WARNINGS AND CAUTIONS
Read all instructions.
1. Always wear safety goggles when working
near batteries. Keep yourself, clothing and test
equipment clear of all moving or hot engine
parts. Be sure ignition is in OFF position, and
all accessories are off before disconnecting bat-
tery.
2. Never place smoking materials, sparks, or
open flames near batteries. Gasoline and bat-
tery gases are highly explosive.
3. Use equipment in locations with adequate
ventilation. Engine exhaust contains carbon
monoxide gas, a colorless, odorless lethal gas.
4. Always disconnect the ground connections
on all batteries before servicing the electrical
system. Be sure all test leads are connected as
instructed before conducting a test.
5. Apply the parking brake, place the gear
selector in neutral (standard transmission)
or park (automatic transmission) and block
the drive wheels. Disable the ignition or
fuel system before performing starting sys-
tem tests.
3
2
Jaw Opening
Trigger
DCmA Zero
Adjust Knob
Power On
Indicator
Power And
Range Selector
Switch
Jaw Opening
Point

MEASURING DC CURRENT
Make sure that the ground and positive leads
are plugged into the proper receptacle for cor-
responding function positions.
Do not attempt to make a
current measurement of
more than 60A or of a cur-
rent that is unknown.
Measurement Procedure:
1. Turn the DMM on and manually set the
DMM rotary switch to 2 or 4 DCV func-
tion.
2. With the A254 connected to the BNC to
banana plug adapter, insert the GND
plug into the COM input jack and the +
plug into the V input jack.
3. Select the desired range on the A254.
4. Using the ZERO knob on the front of
the A254, adjust it until the display on
the DMM reads “0.000”.
5. Clamp the A254 around a single wire to
the circuit to be measured.
6. Read the current on the DMM.
NOTE: Refer to chart on page 5 for read-
ing interpretations
5
READING INTERPRETATION
CHART
4
DMM V 10mV/A 100mV/A
Reading Range Range
0.001 100 mA 10 mA
0.005 500 mA 50 mA
0.010 1.0 amps 100 mA
0.015 1.5 amps 150 mA
0.025 2.5 amps 250 mA
0.050 5.0 amps 500 mA
0.075 7.5 amps 750 mA
0.100 10.0 amps 1 amp
0.125 12.5 amps 1.25 amps
0.150 15.0 amps 1.50 amps
0.175 17.5 amps 1.75 amps
0.200 20.0 amps 2.0 amps
0.250 25.0 amps 2.5 amps
0.300 30.0 amps 3.0 amps
0.350 35.0 amps 3.5 amps
0.400 40.0 amps 4.0 amps
0.450 45.0 amps 4.5 amps
0.500 50.0 amps 5.0 amps
0.550 55.0 amps 5.5 amps
0.600 60.0 amps 6.0 amps
. x .
. x
1.000 x 10.0 amps

APPLICATION:
PARASITIC LOAD ON BATTERY
Measurement Procedure:
1. Turn the DMM on and manually set the
DMM rotary switch to 2 or 4 DCV func-
tion.
2. With the A254 connected to the BNC to
banana plug adapter, insert the GND
plug into the COM input jack and the +
plug into the V input jack.
3. Select the 100mV/A range on the A254.
4. Using the ZERO knob on the front of
the A254, adjust it until the display on
the DMM reads “0.000”.
5. Clamp the A254 around the negative
battery cable.
6. Read the current on the DMM.
7
MEASURING AC CURRENT
Make sure that the ground and positive leads
are plugged into the proper receptacle for cor-
responding function positions.
Do not attempt to make a
current measurement of
more than 60A or of a cur-
rent that is unknown.
Measurement Procedure:
1. Turn the DMM on and manually set the
DMM rotary switch to 2 or 4 ACV func-
tion.
2. With the A254 connected to the BNC to
banana plug adapter, insert the GND
plug into the COM input jack and the +
plug into the V input jack.
3. Select the desired range on the A254.
4. Clamp the A254 around a single wire to
the circuit to be measured.
5. Read the current on the DMM.
NOTE: Refer to chart on page 5 for read-
ing interpretations
6

SPECIFICATIONS
FUNCTION RANGE ACCURACY
DCA
100mV/A 10mA - 20A +/- (1.5% + 20mA)
10mV/A 100mA - 40A +/- (2% + 20mA)
40A - 60A +/- (4% + 20mA)
ACA
100mV/A 10mA - 10A +/- (2% + 20mA)
(40Hz to 1kHz)
+/- (4% + 30mA)
(1kHz to 10kHz)
+/- (8% + 30mA)
(10kHz to 20kHz)
10mV/A 100mA - 40A +/- (2% + 30mA)
(40Hz to 1kHz)
+/- (4% + 30mA)
(1kHz to 2kHz)
+/- (6% + 30mA)
(2kHz to 5kHz)
Operating Temperature 32 to 122 degrees F
Storage Temperature -4 to 158 degress F
Relative Humidity 0 to 80%
Max Conductor Size 9.0mm (0.35 inches)
Power Supply 9 Volt Battery
9
APPLICATION NOTES:
PARASITIC LOAD ON BATTERY
(KOEO- Key Off, Engine Off)
Please refer the figure on page 8
regarding the following notes:
1. Note the reading on the 133 is
-.012 This is becsuse we attached the
A254 to the negative (-) battery cable to
ensure you measure the entire parasitic
draw on the battery. Most new automo-
biles have multiple cables attached to the
positive post that does not allow you to
include all in your measurement.
2. Refering to the chart on page 5, a reading
of .012 DC volts with the A254 set on the
100mV/A range is actually 120mA
(milliamps).
3. Note that the 133 is set on the 2 DCV
range. This is the range the output of the
A254 is designed to use on the 120 and
133 meters. Use the 4 volt range on the
153, 163, 183 and 440.
8

MAINTENANCE
Battery Replacement
1. Set the switch on the front of the
A254 to the OFF position.
2. Unplug the A254 from the DMM or
scope.
3. Remove the 3 screws from the back
of the A254.
4. Separate the front and back housing
and replace the 9 volt battery.
5. Reassemble in reverse order.
Cleaning your A254
Clean the surface area of the A254 with
a mild detergent and damp cloth.
Troubleshooting Guide
No Reading on DMM: Plugged into
incorrect input
jacks. DMM set
to incorrect range
and func-tion
No Power On light: Dead battery
Broken battery
snap wires.
10

Test Products International, Inc.
A254 Instruction Manual
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changes at any time without notice