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MODEL UC 24YFB POWER TOOLS TECHNICAL DATA CHARGER UC 24YFB SERVICE MANUAL LIST No. F846 Mar. 2001 SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT...
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Notice for use Specifications and parts are subject to change for improvement. Refer to Hitachi Power Tool Technical News for further information.
6. PRECAUTIONS IN SALES PROMOTION ..................8 6-1. Safety Instructions .......................... 8 6-2. Extra Precautions in Sales Promotion .................... 9 7. QUESTIONS AND ANSWERS ON MODEL UC 24YFB .............. 10 8. GENERAL PRECAUTIONS ......................12 8-1. Model UC 24YFB .......................... 12 8-2.
Improved stability in mounting battery packs to cordless tools and improved stability in electric contact The Model UC 24YFB Charger that has been developed to meet these needs is capable of recharging either a 24 V slide-in nickel cadmium (Ni-Cd) battery or a 24 V slide-in nickel metal hydride (Ni-MH) battery in about one hour.
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 24YFB is capable of handling both Ni-Cd and Ni-MH batteries. 4-1-2. Rapidly charges Hitachi EB 2420 and 2430 HA batteries Table 1 Recharging time (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 Blinks Prior to charging Stays ON constantly Red pilot lamp During charging Lights remains lit or flashes 0.5 sec.
Approx. 50 minutes (for Ni-Cd 2.0 Ah, 24 V) Product weight 0.6 kg Operating ambient 0 ˚C --- 40 ˚C temperature range 5-2. Comparisons with Similar Products HITACHI UC 24YFB Charging time min. (2.0 Ah, 24 V Ni-Cd) (EB 2420) Charging voltage Charging current 120 V, 2.2 A Power input 120 V, 1.5 A...
6-1. Safety Instructions In the interest of promoting the safest and most efficient use of the Model UC 24YFB 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.
6-2. Extra Precautions in Sales Promotion The following points must be given during sales promotion. 6-2-1. Charging may not be possible when the battery temperature is high Charging may not be possible if the temperature of the battery is high after it has been exposed to direct sunlight for a long time or immediately after it has been used.
7. QUESTIONS AND ANSWERS ON MODEL UC 24YFB Q1 What are typical charging methods? A1 The most recent electronic charging methods are outlined below. Method A Method B UC 12Y UC 24YFA UC 12YA UC 24YFB UC 24YC UC 24YF...
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) to be generated in a short period of time, as shown below. This proportionately accelerates degradation of the plates. microcomputer control system was adopted for the Model UC 24YFB charger in order to stop charging immediately before the battery is fully charged, thereby avoiding the generation of oxygen gas.
8. GENERAL PRECAUTIONS 8-1. Model UC 24YFB (1) The outer frame consists of case (A) and case (B). Inside the frame there are the print circuit board and terminals. (2) The print circuit board consists of high-frequency power transformer, microcomputer and other electronic devices to permit rapid charging and to protect against overcharging.
8-2. Pilot Lamp Indications Pilot lamp indications 0.5 sec. ON 0.5 sec. OFF Blinks Prior to charging Stays ON constantly Red pilot lamp During charging Lights remains lit or flashes Charging 0.5 sec. ON 0.5 sec. OFF Blinks completed 0.1 sec. ON 0.1 sec.
9. PRECAUTIONS IN DISASSEMBLY AND REASSEMBLY The [Bold] numbers in the descriptions below correspond to the item numbers in the Parts List and exploded assembly diagram for UC 24YFB. 9-1. Disassembly (1) Remove the four Tapping Screws (W/Flange) D3 x 20 [6] and take off 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.
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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...
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(4) Trouble mode (D) Pilot lamp flickers red, indicating abnormality. 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. or opened ? Faulty internal circuit Replace PCB.
11. STANDARD REPAIR TIME (UNIT) SCHEDULES Variable 60 min. MODEL Fixed Work Flow UC 24YFB General Assembly Case (A) Case (B) Fuse (3.15 A) Printed Circuit Board Ass'y Light Bar Cord...