IBM iSeries 270 Service Manual page 139

v If you are using the short-circuit test option: Install the test card in DCA location 6 (M38), with no
meter attached.
5. Wait one minute to allow any charge to dissipate.
6. Select the meter to be used for this test. Meters recorded in the Qualified Meters table are to be
used, see Shorts test qualified service meters and fail criteria in this topic. Use the most accurate
meter available.
7. Record the meter model used and the fail criteria for the model. The fail criteria is in the right column
of the qualified meters table. See Shorts test qualified service meters and fail criteria.
8. Calibrate the meter by performing the following:
Note: Do not install the meter in the card at this time.
a. Set the meter to the range defined in the table.
b. Power the meter off and on.
c. Short the meter leads together.
d. Record the meter reading. Call this resistance "Meter Lead Resistance" (MLR).
9. Are MCMs in the system?
v Yes: Continue with the next step.
v No: Install the first MCM module (M21, M16, M11, M14), working top to bottom, cleaning each
LGA site (a load is required before the meter is connected). Then, continue with the next step.
10. Choose from the following options:
v If you are using the new capacitor book option, perform the following:
– Connect the meter "V" to the Capacitor book "TP-2" (MCM).
– Connect the meter "COM" to the Capacitor book "TP-5" (RTN). Then, continue with MCM
installation shorts test, procedure 2 (See page 127).
v If you are using the short-circuit test option, perform the following:
– Connect the meter "V" to the test card "1.6V (yellow jack).
– Connect the meter "COM" to the test card "COMMON RET" (black jack). Then, continue with
MCM installation shorts test, procedure 2 (See page 127).
MCM installation shorts test, procedure 2
1. Choose from the following options:
v If you are using the new capacitor book option: Record the reading while the meter leads are
attached to the Capacitor book. Call this resistance "MCM total resistance" (MCMTR).
v If you are using the short-circuit option: Record the reading while the meter leads are attached to
the test card. Call this resistance "MCM total resistance" (MCMTR).
2. Enter recorded fail criteria*, MLR, MCMTR in the following equation: MCMTR - MLR > Fail criteria.
3. Is the left side of the equation greater than the right side?
v Yes: Continue with the next step.
v No: Go to step 5 (See page 127)
4. Is the left side of the equation greater than 1 Ohm?
v No: Do not power on the system. Contact your next level of support.
This ends the procedure.
v Yes: Are all the MCMs installed?
– Yes: Go to MCM installation shorts test, procedure 3 (See page 128).
– No: Install another MCM/passthru (M21, M16, M11, M14), and go to step 1 (See page 127).
5. Remove the MCM/passthru module.
6. Is this the first time it has been removed?
v Yes: Continue with the next step.
Analyze hardware problems
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