Yaskawa iQpump Controller User Manual - Manual (Page 156)

6.8 Main Circuit Test Procedure
156 YASKAWA TM.iQp.06 iQpump Controller User Manual
Soft Charge Resistor Check
(R1, R2, 6PCB)
The soft charge resistor works in conjunction with the soft charge contactor to slowly charge the DC bus
capacitors to minimize the inrush current when power is applied to the drive.
1. Conduct a visual inspection. Check for physical damage.
2. Set a digital multi-meter to the R x 1 scale.
3. If the resistor is damaged, the measured value will be infinite ohms.
Soft Charge Contactor
(K1)
The purpose of the soft charge contactor is to bypass the soft charge resistor after the DC bus voltage has
reached its normal operating level.
1. Conduct a visual inspection. Check for physical damage.
2. Set a digital multi-meter to the R x 1 scale.
3. On drives with a board-mounted contactor, verify that each contact
resistance measures infinite ohms.
4. On drives without a board-mounted contactor, press the plunger in, and verify that each contact measures 0
ohms.
5. On drives without a board-mounted contactor, release the plunger, and verify that the resistance is the
ohmic value of the soft charge resistor.
6. On drives with a board-mounted contactor, verify that the contactor coil measures about 300 ohms. The
coil can be tested by applying the appropriate voltage to verify the contacts change states.
7. On drives without a board-mounted contactor, verify that the 230 Vac contactor coil measures about 175
ohms. The coil can be tested by applying the appropriate voltage to verify the contacts change states.
8. On drives without a board-mounted contactor, verify that the 24 Vdc auxiliary coil measures about 2.2 M
ohms. The coil can be tested by applying the appropriate voltage to verify the contacts change states.
DC Bus Fuse
(F1)
The DC bus fuse is located in the negative portion of the DC Bus. The DC bus fuse is used to protect the main
circuit components if the output transistors short. If the DC bus fuse is open, at least one of the output
transistors has failed. When a transistor fails, there is a short between the positive and negative portions of the
DC Bus. The DC bus fuse does not protect the transistors, but protects the rest of the main circuit from the high
current present during a short. Never replace the DC bus fuse without first checking all of the output
transistors.
1. Set a digital multi-meter to the R x 1 scale.
2. Place one lead of the multi-meter on one side of the fuse and place the other lead of the multi-meter on the
other side of the fuse.
3. If the fuse is good, the measured value will be 0 ohms.
4. If the fuse is bad, the measured value will be infinite ohms.
Output Transistors
(Q1-Q12)
The output transistors are used to switch the DC bus voltage to allow current to flow to the motor.
1. Set a digital multi-meter to the Diode Check setting.
2. Place the positive (red) meter lead on terminal U/T1.
Place the negative (black) meter lead on terminal ⊕ 1.
Expected reading is about 0.5 Volts.
3. Place the positive (red) meter lead on terminal V/T2.
Place the negative (black) meter lead on terminal ⊕ 1.
Expected reading is about 0.5 Volts.
4. Place the positive (red) meter lead on terminal W/T3.
Place the negative (black) meter lead on terminal ⊕ 1.
Expected reading is about 0.5 Volts.
5. Place the positive (red) meter lead on terminal U/T1.
Place the negative (black) meter lead on terminal (-).
Expected reading is OL displayed.
6. Place the positive (red) meter lead on terminal V/T2.
Place the negative (black) meter lead on terminal (-).
Expected reading is OL displayed.
7. Place the positive (red) meter lead on terminal W/T3.
Place the negative (black) meter lead on terminal (-).
Expected reading is OL displayed.
8. Place the positive (red) meter lead on terminal (-).
Place the negative (black) meter lead on terminal U/T1.
Expected reading is about 0.5 Volts.
9. Place the positive (red) meter lead on terminal (-).
Place the negative (black) meter lead on terminal V/T2.
Expected reading is about 0.5 Volts.
10. Place the positive (red) meter lead on terminal (-).
Place the negative (black) meter lead on terminal W/T3.
Expected reading is about 0.5 Volts.
Check Procedure