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MODEL UC 24YC POWER TOOLS TECHNICAL DATA CHARGER UC 24YC SERVICE MANUAL LIST No. F840 Jun. 2000 SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT...
The Model UC 24YC will be sold as an accessory for after market purposes. Plans to bundle it with electric power tools will be put on hold for the time being because the Model UC 24YC is more costly than the Model UC 24YF.
24 V, 3.0 Ah 60 minutes • • • • • • • • • (3) Hitachi original charge control mechanism for longer battery life. Recharging/discharging cycles of battery (ambient temperature range between 10 ˚C and 30 ˚C) • Ni-Cd: about 1,000 times •...
4-1. Selling Point Descriptions 4-1-1. Capable of handling both nickel cadmium (Ni-Cd) and nickel metal hydride (Ni-MH) batteries Through application of HITACHI-microcomputer and electronic-circuit control technology, Model UC 24YC is capable of handling both Ni-Cd and Ni-MH batteries. 4-1-2. Rapidly charges all Hitachi EB-series batteries: Recharging time for EB 2430H battery has been reduced to approx.
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4-1-5. 3-way overcharge protection system Overcharge protection is ensured by a (A) system or dT/dt system (for Ni-MH battery), (B) built-in battery temperature sensors (thermostat and thermistor) and (C) a timer. Overcharge range Battery voltage 55˚C Thermistor dT/dt 60˚C Thermistor 40˚C Thermostat Ni-MH Battery temperature...
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4-1-6. Easy-to-read visual display of charging status through constant lighting or flashing of red and green pilot lamps Pilot lamp indications 0.5 sec. ON 0.5 sec. OFF Prior to charging Blinks Stays ON constantly Red pilot lamp During charging Lights remains lit or flashes Charging...
6-1. Safety Instructions In the interest of promoting the safest and most efficient use of the Model UC 24YC Charger by all of our customers, it is very important that at the time of sale the salesperson carefully ensures that the buyer seriously recognizes the importance of the contents of the Handling Instructions.
(1) Because the shape of the B-2 (7.2 V) battery is different from others, it cannot be connected to the Model UC 24YC. (2) Even if the B-3 (9.6 V) battery is connected to the Model UC 24YC using the optional accessory adapter, recharging is not possible because the internal wiring of the battery is different from the others.
7. QUESTIONS AND ANSWERS ON MODEL UC 24YC Q1 What are typical charging methods? A1 The most recent electronic charging methods are outlined below. Method A Method B UC 12Y UC 24YC UC 12YA UC 24YF UC 14YF2 UC 14YF...
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Q2 Why was the microcomputer control system adopted for the Model UC 24YC? A2 If charging is continued after the battery has been fully charged, it will cause a large amount of oxygen gas ) to be generated in a short period of time, as shown below. This proportionately accelerates degradation of the plates.
8. GENERAL PRECAUTIONS 8-1. Model UC 24YC (1) The outer frame consists of case (A) and case (B), and houses a printed circuit board (PCB). (2) The charging terminals, high-frequency power transformer, microcomputer controller ICs, etc., are mounted on the upper surface of the PCB.
8-2. Wiring Diagram Charging output terminals Case (B) (PCB) TAB terminal 8-3. Pilot Lamp Indications Pilot lamp indications 0.5 sec. ON 0.5 sec. OFF Prior to charging Blinks Stays ON constantly Red pilot lamp During charging Lights remains lit or flashes 0.5 sec.
9. PRECAUTIONS IN DISASSEMBLY AND REASSEMBLY The [Bold] numbers in the descriptions below correspond to the item numbers in the Model UC 24YC Parts List and exploded assembly diagram. 9-1. Disassembly Remove the four Tapping Screws (W/Flange) D3 x 20 [7], and separate Case (B) Ass'y [6] and Case (A) [2].
10. TROUBLESHOOTING GUIDE 10-1. Troubleshooting Based on Pilot Lamp Indications Phenomenon Typical causes Check procedures Pilot lamp fails to light or flash. (1) Faulty AC cord Refer to trouble mode (A). (2) Blown fuse (3.15 A) on primary side Red pilot lamp does not stay lit (1) Poor connection of (T) or (S) terminal Refer to trouble mode (B).
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(2) Trouble mode (B) Red pilot lamp does not stay lit (continues to flash) after battery has been connected. Are the connection terminals Remove dirt or of the charger or the battery dirty, deformed, correct abnormality. or otherwise abnormal ? Check with tester S, G, B, M and H-type batteries: Is the...
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(3) Trouble mode (C) Pilot lamp remains green (red fails to light) after battery has been connected. Is ambient temperature Conduct charging within within designated range (between designated temperature range. 0˚C and 40˚C) ? 0˚C 40˚C Is the Allow battery to cool prior to battery very charging hot ?
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(4) Trouble mode (D) Pilot lamp flickers red, indicating abnormality. Is the battery Install battey in correct connected in reverse direction. direction ? Is there some sort of conductive foreign Remove foreign matter. matter in the hole where the battery is inserted ? Is the battery short-circuited Replace the battery.
11. STANDARD REPAIR TIME (UNIT) SCHEDULES Variable 60 min. MODEL Fixed Work Flow UC 24YC General Assembly Case (A) Case (B) Fuse (3.15 A) Cord Prism Varistor Terminal (A) Terminal (B) --- 20 ---...