Precautions On Disassembly And Reassembly; Disassembly; Reassembly; Confirmation After Reassembly - Hitachi UC 18YK Technical Data And Service Manual

8. PRECAUTIONS ON DISASSEMBLY AND REASSEMBLY

[Bold] numbers in the descriptions below correspond to item numbers in the Parts List and exploded
assembly diagram for the Model UC 18YK.

8-1. Disassembly

(1) Remove the four Tapping Screws (W/Flange) D3 x 18 [7], and then take off Case (A) [1].
The Printed Circuit Board Ass'y [4] and Cord [2] can then be removed as an assembled body.
(2) To separate the Printed Circuit Board Ass'y [4] and Cord [2], use a soldering iron to melt the soldered
portions.
(NOTE) Ideally, a solder absorber is recommended for freeing the soldered portions. When a soldering iron
must be used, use one with rated power of 35 W.

8-2. Reassembly

Reassembly can be performed by reversing the disassembly procedure; however, make certain that the
pilot lamp, cord armor and charging terminals are properly installed in the prescribed grooves.

8-3. Confirmation after Reassembly

(1) Confirm the following after reassembly. The red pilot lamp on the charger lights when charging is
started.
• When charging an EB 1820L battery, confirm that the pilot lamp goes off in about 80 minutes after
starting charging operation.
(2) Measure the insulation resistance and conduct a dielectric strength test.
• Insulation resistance:
• Dielectric strength test:
(a) Between one plug blade of the cord and one charging terminal blade
(b) Between one plug blade of the cord and the Name Plate or fastening screws on the case
Based on the voltage listed on the Name Plate, dielectric strength test should be conducted.
Voltage on the Name Plate
(CAUTION) Without fail, insulation resistance must be measured between one plug blade of the
cord and the Name Plate or fastening screws; dielectric strength test must be
conducted between one plug blade of the cord and one charging terminal blade, or
between one plug blade of the cord and the Name Plate or fastening screws on the
case. Under no circumstances should testing be conducted between both plug
blades or both charging terminal blades. Doing so could burn out the charger.
10 MΩ or more between the plug blade of the cord and the Name Plate or
case fastening screws, using a DC 500 V megohm tester.
120 V
220 V to 240 V
Test Voltage
AC 1,240 V (1 minute)
AC 3,750 V (1 minute)
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