Hitachi DH 24DVA Manual

TECHNICAL DATA
AND
SERVICE MANUAL
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
LIST No. G842 Mar. 2006
D
MODEL
DH 24DVA
Hitachi 
Power Tools
CORDLESS ROTARY HAMMER
DH 24DVA

Symbols Utilized
Competitors
Company Name Model Name
DEWALT DW005K
P
MAKITA BHR200
C
REMARK:
Throughout this TECHNICAL DATA AND SERVICE MANUAL, a symbol(s)
is(are) used in the place of company name(s) and model name(s) of our
competitor(s). The symbol(s) utilized here is(are) as follows:

Page
CONTENTS
1. PRODUCT NAME ............................................................................................................................ 1
2. MARKETING OBJECTIVE .............................................................................................................. 1
3. APPLICATIONS ............................................................................................................................... 1
4. SELLING POINTS ........................................................................................................................... 2
4-1. Selling Point Descriptions ................................................................................................................ 2
5. SPECIFICATIONS ........................................................................................................................... 4
5-1. Specifications ....................................................................................................................................4
5-2. Optional Accessories ........................................................................................................................6
6. COMPARISONS WITH SIMILAR PRODUCTS .............................................................................. 11
6-1. Specification Comparisons ............................................................................................................. 11
6-2. Drilling Speed Comparisons ...........................................................................................................12
6-3. Chiseling Performance Comparison ...............................................................................................13
6-4. Per Charge Working Capacity Comparisons ..................................................................................14
7. PRECAUTIONS IN SALES PROMOTION .................................................................................... 15
7-1. Handling Instructions ......................................................................................................................15
7-2. Caution Plates ................................................................................................................................17
7-3. Precautions Requiring Particular Attention During Sales Promotion ..............................................18
8. REFERENCE MATERIAL .............................................................................................................. 19
8-1. Lubrication ......................................................................................................................................19
8-2. Tool Structure ..................................................................................................................................19
8-3. "Three-Mode" Changeover Mechanism ..........................................................................................23
8-4. "Rotation Only" (No Hammering) ....................................................................................................25
8-5. Drill Bits ...........................................................................................................................................26
8-6. Tool Retainer Section ......................................................................................................................27
8-7. Dust Collector (B) ...........................................................................................................................28
9. PRECAUTIONS IN DISASSEMBLY AND REASSEMBLY ........................................................... 29
9-1. Disassembly ...................................................................................................................................29
9-2. Reassembly ....................................................................................................................................32
9-3. Precautions on Disassembly and Reassembly of the Charger .......................................................35
10. STANDARD REPAIR TIME (UNIT) SCHEDULES ...................................................................... 36
Assembly Diagram for DH 24DVA

--- 1 ---
1. PRODUCT NAME
Hitachi Cordless Rotary Hammer, Model DH 24DVA
2. MARKETING OBJECTIVE
The new Model DH 24DVA is a 3-mode type cordless rotary hammer based on the current Model DH 24DV.
It features not only "rotation + hammering" mode and "rotation only" mode but also "hammering only" mode for
chiseling and groove digging. The Model DH 24DVA has the same cylindrical gear cover as that of the current
Model DH 24DV because its toughness is well reputed. The applicable batteries are the Type EB 2420 and
EB 2433X, and the applicable charger is the Model UC 24YFB. The main components of the hammering
mechanism are common with the Model DH 24PC3 and the power supply unit including the motor is common with
the Model DH 24DV. Our rotary hammer lineup is reinforced with the new Model DH 24DVA aiming for increase of
our market share.
3. APPLICATIONS
(1) Rotation and hammering function
Drilling anchor holes
Drilling holes in concrete, tile, brick and similar materials
(2) Rotation only function
Drilling holes in steel and wood (with chuck adapter)
Tightening and loosening machine screws and wood screws (with chuck adapter)
(3) Hammering only function
Light-duty chiselling of concrete
Groove digging and edging
[Typical applications]
Air conditioning...................................... Installation of air conditioners, water coolers and heaters, and air ducts
Piping and plumbing ............................. Installation of gas, water, and sanitary facilities
Electrical work ....................................... Installation of light fixtures and various electric appliances
Interior decoration ................................. Installation of seating, display stands and partitions
Other civil engineering, construction and repair work

--- 2 ---
4. SELLING POINTS
Fastest drilling speed in the 24-V class
Equivalent to the Model DH 24DV
1.4 times faster than P and C
Greatest demolishing
performance in the 24-V class
1.4 times higher than C
1.1 times higher than P
Internal pressure
adjustment mechanism
Selectable from 3 modes
"Hammering only" mode is available.
(Model DH 24DV: 2-mode type)
4-1. Selling Point Descriptions
4-1-1. Selectable from 3 modes, "rotation + hammering", "rotation only" and "hammering only"
The new Model DH 24DVA is a 3-mode type cordless rotary hammer based on the Model DH 24DV cordless
rotary hammer drill (2-mode type). It features the "hammering only" mode in addition to the "rotation +
hammering" mode and the "rotation only" mode. The "hammering only" mode is available not only for light-duty
chipping by means of bull points but also for groove digging and edging by means of cold chisels and cutters for
various applications.
4-1-2. Fastest drilling speed in the 24-V class
The drilling speed of the Model DH 24DVA is equivalent to the Model DH 24DV and 1.4 times higher than C and
1.1 times higher than P thanks to the efficient transmission of the hammering energy. For detail, refer to "6-2.
Drilling Speed Comparisons" on page 12.
Switchable hammering force mechanism increases working efficiency.
POWER mode: For drilling holes in 5 mm or more diameter
Powerful and quick drilling
For chiseling hard materials such as concrete
SAVE mode: For drilling holes in 4.8 mm or less diameter
Prevents the bit from being bent
For chiseling brittle materials such as blocks and bricks

--- 3 ---
Change lever
Shift knob
"Rotation + hammering"
"POWER"
mode
(Powerful
hammering
force)
"SAVE"
mode
(Suppressed
hammering
force)
<Drilling holes in concrete>
<Drilling holes in concrete>
Suitable for drilling holes
in 5 mm or more diameter
with high motor power
(speedy and efficient
drilling)
Suitable for drilling holes
in 4.8 mm or less diameter
with suppressed motor
power (preventing the bit
from being bent)
"Hammering only"
"Rotation only"
<Drilling holes in steel and wood>
<Nonusable>
Suitable for drilling holes
in steel and wood
speedily with high motor
power
Do not use the Model
DH 24DVA for high-load
operation in this mode
because the motor power
is suppressed.
(Otherwise, the motor
may be burnt out.)
<Demolishing concrete>
<Demolishing blocks>
Suitable for demolishing
hard materials such as
concrete with high motor
power
Suitable for demolishing
brittle materials such as
blocks and bricks with
suppressed motor power
4-1-3. Greatest demolishing performance in the 24-V class
The demolishing performance of the Model DH 24DVA is 1.4 times higher than C and 1.1 times higher than P
thanks to the efficient transmission of the hammering energy.
4-1-4. Internal pressure adjustment mechanism
By minimizing variations in the internal pressure during operation, hammering operation is stabilized. In addition,
idling and grease leakage can be prevented.
4-1-5. Switchable hammering force mechanism increases working efficiency
The Model DH 24DVA is equipped with the same mechanism as the Model DH 24DV to switch the hammering
force between "POWER" mode and "SAVE" mode for proper adjustment of the hammering force.

--- 4 ---
Sealed power source: Single-phase AC, 50/60 Hz
Voltage: Depending on the order specification
Power input: 90 W
Charging system: Constant current charge with full wave phase control
Overcharge protection system: (1) Battery voltage detection ( 2V system)
for EB 2420 battery
Ni-MH battery temperature detection
(dT/dt system) for EB 2433X battery
(2) Battery surface temperature detection
(thermistor)
(3) 120 minutes timer
Output voltage: DC 24V
Output current: 2.5 A
Charging time: Approx. 50 minutes (for EB 2420 at 20ûC (68ûF))
Approx. 75 minutes (for EB 2433X at 20ûC (68ûF))
Operable ambient temperature range: 0ûC --- 40ûC (32ûF --- 104ûF)
The maximum allowable temperature of the Model EB 2420 battery is 60ûC
(140ûF) and the Model EB 2433X battery is 45ûC (113ûF).
Weight
"POWER" mode: 4,500/min., "SAVE" mode: 2,200/min.
Main body 4.1 kg (9.0 lbs.) (with battery)
Battery EB 2420 1.3 kg (2.87 lbs.)
EB 2433X 1.4 kg (3.09 lbs.)
Charger UC 24YFB 0.6 kg (1.3 lbs.)
Type of motor DC magnet motor
No-load rotation speed "POWER" mode: 1,050/min., "SAVE" mode: 520/min.
Type of switch Trigger switch with forward/reverse rotation selector (with brake)
D-type handle with side handle
Handle shape
5. SPECIFICATIONS
5-1. Specifications
Capacity
Usable drill bits
24 mm (15/16")
SDS-plus type only
13 mm (1/2")
30 mm (1-3/16")
Concrete
Steel
Wood
Full-load blow
Enclosure
Body Glassfiber reinforced polyamide resin ••••Housing, gear cover
Glassfiber reinforced polycarbonate resin and thermoplastic
elastomer •••••••••••••••••••••••••••••••••••••••••••• Grip cover
Aluminum alloy die casting ••••••••••••••••••• Inner cover
Battery Glassfiber reinforced polyamide resin
Charger ABS resin
Battery
(Type EB 2420)
Sealed cylindrical nickel cadmium storage battery
Nominal voltage: DC 24V
Nominal life: Charging/discharging approximately 1,000 cycles
(in the case of the Model UC 24YFB)
Nominal capacity: 2.0 Ah
Battery
(Type EB 2433X)
Sealed cylindrical nickel-metal hydride storage battery
Nominal voltage: DC 24V
Nominal life: Charging/discharging approximately 750 cycles
(in the case of the Model UC 24YFB)
Nominal capacity: 3.3 Ah
Charger
(Model UC 24YFB)

--- 5 ---
Charger (depending on order specifications) ••••••••••••••••••••••••••••••••••••••••••••••••• 1 unit
Side handle •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1 pc.
Plastic case •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1 pc.
Depth gauge ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1 pc.
Red pilot lamp
remains lit or flashes.
Green pilot lamp is lit.
Storage battery or
charger is faulty.
During charging
Prior to charging
Charging completed
High battery
temperature
Standard
accessories
Charging not
possible
Charging not possible
because storage battery
temperature is too high.
Blinks
Blinks
Lit
Lit
Flickers
0.5 sec. ON, 0.5 sec. OFF
0.5 sec. ON, 0.5 sec. OFF
Stays ON constantly
0.1 sec. ON, 0.1 sec. OFF
Stays ON constantly
Pilot lamp indications (UC 24YFB)

--- 6 ---
5-2. Optional Accessories
A. Drilling anchor holes (rotation + striking)
(1) Drill bit (slender shaft)
(1) Drill bit (taper shank)
Outer dia. (mm)
11 (7/16")
12.3 (31/64")
12.7 (1/2")
14.3 (9/16")
14.5 (73/128")
17.5 (11/16")
Code No.
944460
944461
993038
944462
944500
944463
(2) Taper shank adapter
Type Code No.
Morse taper
No. 1 303617
(3) Cotter
Code No.
944477
3.4 (1/8")
3.5 (9/64")
Outer dia. (mm) Effective length (mm)
45 (1-25/32")
45 (1-25/32")
(2) Adapter for slender shaft
(SDS-plus shank)
Drill bit (slender shaft)
90 (3-17/32")
90 (3-17/32")
Overall length (mm) Code No.
306369
306368
306370
Code No.
Adapter for slender shaft
Drill bit (slender shaft)
(1) Drill bit (taper shank) (2) Taper shank adapter
(SDS-plus shank)
Drill bit (taper shank)
21.5 (27/32") 944464 Morse taper No. 2 303618
(3) Cotter
Straight-shank bit for
impact drills
13 mm (1/2") hammer drill
chuck (SDS-plus shank)
13 mm hammer drill chuck
For drilling operations when using a straight shank bit for impact drilling with a hammer drill
Chuck wrench
303619
303620
Taper-shank adapter (A-taper or B-taper) is provided as an
optional accessory, but drill bit is not provided.
A-taper
B-taper
Code No.Part name
Chuck wrench
Rubber cap
Part name
303332
303334
303335
13 mm (1/2") hammer drill chuck
(including chuck wrench)
Code No.
Rubber cap

--- 7 ---
B. Anchor setting
Anchor setting adapter (SDS-plus shank)
Part name
W-1/4 Anchor setting adapter-A
W-5/16 Anchor setting adapter-A
W-3/8 Anchor setting adapter-A
W-3/8 Anchor setting adapter-A
Code No.
302976
302975
303621
302974
Anchor setting bar to permit anchor setting operation with the hammer drill
Overall length
260
260
160
260
Part name
W-1/4 Anchor setting adapter-B
W-5/16 Anchor setting adapter-B
W-3/8 Anchor setting adapter-B
W-3/8 Anchor setting adapter-B
Code No.
302979
302978
303622
302977
Overall length
260
260
160
260
Internal cone type External cone type
Anchor setting bar for manual anchor setting
Anchor setting adapter
Part name
W-1/4 Anchor setting adapter-A
W-5/16 Anchor setting adapter-A
W-3/8 Anchor setting adapter-A
W-1/2 Anchor setting adapter-A
W-5/8 Anchor setting adapter-A
Code No.
971794
971795
971796
971797
971798
Part name
W-1/4 Anchor setting adapter-B
W-5/16 Anchor setting adapter-B
W-3/8 Anchor setting adapter-B
W-1/2 Anchor setting adapter-B
W-5/8 Anchor setting adapter-B
Internal cone type External cone type
Code No.
971799
971800
971801
971802
971803
Anchor setting bar
C. Bolt placing operations with chemical anchor (rotation + hammering)
12.7 mm (1/2") Chemical anchor adapter (SDS-plus shank)
19 mm (3/4") Chemical anchor adapter (SDS-plus shank)
Part name
12.7 mm (1/2") Chemical anchor adapter
19 mm (3/4") Chemical anchor adapter
Code No.
303044
303045
(Standard sockets available on the market)
Bull point (round type)
(SDS-plus shank)
Square bull point
(SDS-plus shank)
D. Crushing operations (hammering only)
Code No. 303046 Code No. 316656