ATTENTION: Never
attempt to open this instrument, unless you’re familiar with repairing
measuring instruments. This is a very delicate
and accurate measuring instrument and somewhat costly too.
Battery operating time is does not meet the
specification (4 hours)
1. Turn the ScopeMeter on (battery power only)
2. Check the voltage across R4101 (near the battery connector) for about 140 mV. This corresponds to a current of about 0.95 A. If the current is much higher the cause of the problem is not the battery.
Battery is discharged when ScopeMeter is not used for some time (2 or 3 weeks).
1. Turn the ScopeMeter on (battery power only)
2. Check the voltage across R4101 (near the battery connector) for about 140 mV. This corresponds to a current of about 0.95 A. If the current is much higher the cause of the problem is not the battery.
Battery is discharged when ScopeMeter is not used for some time (2 or 3 weeks).
1. Turn the ScopeMeter on (battery power only)
2. Check the voltage across R4101 (near the battery connector) for about 0.15 mV. This corresponds to a current of about 1 mA. Turn the ScopeMeter off and on, and check the voltage again for 0.15 mV. Do this about 10 times. If one or more times a current of about 1.2 mV is measured (8 mA), the cause is a defective IC D3550. This IC takes care of a correct power state of D3500. As the 8 mA discharge current can have damaged the battery, you must check the battery capacity as described below.
3. If the current is much higher then 8 mA the cause of the problem is not or is not only D3550
2. Check the voltage across R4101 (near the battery connector) for about 0.15 mV. This corresponds to a current of about 1 mA. Turn the ScopeMeter off and on, and check the voltage again for 0.15 mV. Do this about 10 times. If one or more times a current of about 1.2 mV is measured (8 mA), the cause is a defective IC D3550. This IC takes care of a correct power state of D3500. As the 8 mA discharge current can have damaged the battery, you must check the battery capacity as described below.
3. If the current is much higher then 8 mA the cause of the problem is not or is not only D3550
To check if the battery has a correct capacity
1. Do a battery refresh
1. Do a battery refresh
2. Disconnect the BC190 Battery Charger/Power Adapter
3. Start a TrendPlot: RECORDER
4. When the battery is discharged the ScopeMeter will shut down. Now connect the BC190, turn the power on and check the length of the TrendPlot trace. For a new battery pack this should be about 4 hours. Depending on the number of applied charge cycles the battery capacity will decrease. If the TrendPlot trace has a length of 3 hours or less you may consider to replace the battery pack.
3. Start a TrendPlot: RECORDER
4. When the battery is discharged the ScopeMeter will shut down. Now connect the BC190, turn the power on and check the length of the TrendPlot trace. For a new battery pack this should be about 4 hours. Depending on the number of applied charge cycles the battery capacity will decrease. If the TrendPlot trace has a length of 3 hours or less you may consider to replace the battery pack.
Loading Software
To load a new software version in the test tool contact an authorized Fluke Service center.
To load a new software version in the test tool contact an authorized Fluke Service center.
ELPLODED VIEW
FLY-BACK CONVERTER
1. Check the fly back converter output voltages +5V2, +3V3GAR (+3.3 V),
+3V45, +2V6, -1V8, -5V2 and +30V. Check
FLTPOWIN1and FLTPOWIN2 (6.5Vrms, ≈ 70 kHz) on for example T1102 pin 3 and pin
5.
a.If one or more voltages are correct, then check the rectifier
diodes, coils, and capacitors of the incorrect voltage (s)
b. If none of the voltages is correct, then the fly back converter does not run correctly, continue at step 2.
2. Check VBATT for >7 V.
3. Check N4000:49 (FLYGATE) for a square wave voltage of at least some volts (for a correct Fly Back Converter 50...100 kHz, ≅8 Vpp). If no square wave is present on N4000:49 go to step 4. If a square wave is present on pin 49 (maybe not the correct value), then check N4000:55 (FLYSENSP) for a saw tooth voltage of 50...100 kHz, 300 mVpp.
b. If none of the voltages is correct, then the fly back converter does not run correctly, continue at step 2.
2. Check VBATT for >7 V.
3. Check N4000:49 (FLYGATE) for a square wave voltage of at least some volts (for a correct Fly Back Converter 50...100 kHz, ≅8 Vpp). If no square wave is present on N4000:49 go to step 4. If a square wave is present on pin 49 (maybe not the correct value), then check N4000:55 (FLYSENSP) for a saw tooth voltage of 50...100 kHz, 300 mVpp.
a. If no sawtooth voltage is present on N4000:55, no current or a
DC current flows in FET V4001. The primary coil of T4001 or V4001 may be
defective. Check also R4101 (current sense resistor); it can be fused due to a
short in FET V4001.
b. An incorrect sawtooth on N4000:55 can be caused by:
* overloaded outputs (Frequency too low, <<50 kHz)
* underloaded outputs (Frequency too high, >>100 kHz)
* bad FET V4001 (Sawtooth voltage is not linear).
4. Check N4000:62 (PWRONOFF) for >+3V. If wrong, see Section 7.5.13 Power ON/OFF.
5. Check N4000:43 (COSC) for a triangle wave form, 50...100 kHz, +1.6 V to +3.2 V. If wrong check C4123 and connections; check IREF, see step 6.
If all correct, then replace N4000.
6. Check N4000:74 (IREF) for 1.6 V. If wrong:
a. Check N4000:73 (REFPWM2) for +3V3. REFPWM2 is supplied by N4000, and derived from REFP. Check N4000:72 (REFP) for 1.22 V. If wrong, check V4114 and connected parts.
b. Check R4021, replace N4000.
7. Check N4000:51 (VOUTHI) for <2.5 V (nominal value 1.8 V). If wrong check R4014 and connections to N4000.
8. Check N4000:57 (IMAXFLY) for 570 mV. If wrong check R4020 and connections to N4000.
b. An incorrect sawtooth on N4000:55 can be caused by:
* overloaded outputs (Frequency too low, <<50 kHz)
* underloaded outputs (Frequency too high, >>100 kHz)
* bad FET V4001 (Sawtooth voltage is not linear).
4. Check N4000:62 (PWRONOFF) for >+3V. If wrong, see Section 7.5.13 Power ON/OFF.
5. Check N4000:43 (COSC) for a triangle wave form, 50...100 kHz, +1.6 V to +3.2 V. If wrong check C4123 and connections; check IREF, see step 6.
If all correct, then replace N4000.
6. Check N4000:74 (IREF) for 1.6 V. If wrong:
a. Check N4000:73 (REFPWM2) for +3V3. REFPWM2 is supplied by N4000, and derived from REFP. Check N4000:72 (REFP) for 1.22 V. If wrong, check V4114 and connected parts.
b. Check R4021, replace N4000.
7. Check N4000:51 (VOUTHI) for <2.5 V (nominal value 1.8 V). If wrong check R4014 and connections to N4000.
8. Check N4000:57 (IMAXFLY) for 570 mV. If wrong check R4020 and connections to N4000.
BACK-LIGHT
MAIN
CLICK ON THE PICTURES TO ZOOM IN
