56-101-00901 Revision F
Page 11
J. Disconnect the TT1000A and return the aircraft to its original configuration.
4. THERMOCOUPLE RESISTANCE TEST PROCEDURE
A. Disconnect lead wires from the engine thermocouple terminals.
B. Carefully connect test lead clips to each of the terminals insuring a good electrical connection.
C. Rotate the FUNCTION selector to RESISTANCE MEASURE.
D.
Rotate the RESISTANCE RANGE selector to 20Ω.
E. Place the ON / OFF switch to ON and depress the BLACK pushbutton switch.
F.
Display will indicate resistance in ohms to within 0.01 Ω.
G. If a "1_.__
" is displayed, select 200Ω on the RESISTANCE RANGE switch. If a "1__._" is
displayed, resistance is greater than 199.9Ω or there is an open circuit.
H. Swap the RED and BLACK test clip connections and the display should repeat when the
BLACK pushbutton is depressed. If the reading does not repeat, the engine thermocouple may
be hot (refer to paragraph. 2.D.
on page 10).
Note:
Resistance must be within manufacturer's specifications. If results are slightly outside
limits, repeat entire procedure to ensure test failure is not due to human error.
I. Place the ON / OFF switch to OFF.
J. Disconnect the TT1000A and return the aircraft to its original configuration.
5. INSULATION TESTING PROCEDURE
A. Disconnect one or both leads at system temperature indicator. Then connect the BLACK lead
clip to ground and the RED lead clip to one or both thermocouple system lead wires (refer to
engine manufacturers' Maintenance Manual for specific connections).
B. Rotate the FUNCTION selector to RESISTANCE MEASURE.
C.
Rotate the RESISTANCE RANGE selector to 2MΩ (0Ω SYS. RES.).
D. Place the ON / OFF switch to ON and depress the BLACK pushbutton switch.
E. Dis
play will indicate insulation resistance in 1,000,000's of ohms (MΩ). If a "1.__" is displayed,
insulation resistance is above 2MΩ (refer to the Aircraft Maintenance Manual for low limit).
Note:
Resistance to ground must not be less than manufacturer's specifications.
F. Place the ON / OFF switch to OFF.
G. Disconnect the TT1000A and return the aircraft to its original configuration.