Hitachi DH 28PC Manual

PRODUCT NAME
Hitachi Rotary Hammer
Model DH 28PC
[ NEW FEATURES ]
Most compact body in its class
Highest demolition performance in its class
Equipped with a reversing switch
[ SAME FEATURES AS CONVENTIONAL MODELS ]
3-mode changing and variable lock mechanism fo
r
easy working-angle adjustment of chisels, etc.
Idle striking prevention mechanism with catch
-
ring method
One push type of bit mounting
Internal pressure adjustment mechanism
Easy-to-operate and double-molded switch handle
and side handle
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.
This product features a maximum bit diameter of 28 mm, the capability to drill holes in concrete and other hard
materials, the mounting SDS-plus shank bits," and three modes (Rotation + Hammering, Rotation only, and
Hammering only) that enable chipping and groove-cutting work. This 3-mode type of product offers improved
drilling/chipping performance, as well as reduced product size and weight. This product together with the dust-
collection type of product (DH 28PD) developed at the same time forms a continuous lineup of D-shaped handle
rotary hammer drills in order to promote the sharing of these products.
(1) Rotation and hammering function
• Drilling anchor holes. Drilling holes in concrete, tile, brick and similar materials. Large hole boring with core bit.
(2) Rotation only function
• Drilling holes in steel and wood (with chuck adapter). Tightening machine screws and wood screws
(with chuck adapter).
(3) Hammering only function
• Stripping mortar and tiles. Demolishing and chiseling of concrete. Grooving and cutting of bricks.
MARKETING OBJECTIVE
APPLICATIONS
SELLING POINTS
D
LIST No. F408
Dec. 2009
Sales Division

REMARK:
• For more information about HANDLING INSTRUCTIONS, visit our website at:
http://www.hitachi-koki.com/manual_view_export/
• 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:
Competitors
Symbols Utilized
Company Name Model Name
B BOSCH GBH3-28E
C MAKITA HR2811F

CONTENTS
Page
SELLING POINTS ------------------------------------------------------------------------------------------------------------- 1
SPECIFICATIONS ------------------------------------------------------------------------------------------------------------- 4
1. Specifications----------------------------------------------------------------------------------------------------- 4
2. Optional Accessories ------------------------------------------------------------------------------------------- 5
COMPARISON WITH SIMILAR PRODUCTS--------------------------------------------------------------------------10
1. Comparison of Specifications----------------------------------------------------------------------------------------------------- 10
2. Comparison of Drilling Speed ---------------------------------------------------------------------------------------------------- 11
PRECAUTIONS ON SALES PROMOTION ----------------------------------------------------------------------------12
1. Safety Instructions ---------------------------------------------------------------------------------------------12
REFERENCE MATERIALS-------------------------------------------------------------------------------------------------13
REPAIR GUIDE----------------------------------------------------------------------------------------------------------------17
1. Precautions on Disassembly and Reassembly ---------------------------------------------------------17
STANDARD REPAIR TIME (UNIT) SCHEDULES--------------------------------------------------------------------29
Assembly Diagram for DH 28PC

-1-
C: Outlined shape
B: Outlined shape
HITACHI DH 28PC: 316 mm (for C: -4 mm, for B: -16 mm)
C: 320 mm
B: 332 mm
HITACHI DH 28PC, B: 208 mm
(C: -17 mm)
C: 225 mm
HITACHI DH 28PC shape
Most compact body in its class
By downsizing and optimizing the motor and mechanism components, Hitachi significantly reduced overall
product length to achieve the most compact body in this class of product.
Model HITACHI
DH 28PC CB
Full length (mm) 316 320 332
SELLING POINTS
*Based on our own research

-2-
• Comparison of chiseling amounts (Test results obtained at Hitachi factory)
* The chiseling amount is dependent upon test conditions.
* “C” has no "Hammering" mode.
05101520 25 30
C
25.2
18.2
HITACHI
DH 28PC
Highest demolition performance in its class
Hitachi achieved the highest demolition performance in this class of product by optimizing the hammering
properties.
Equipped with a reversing switch
This product is equipped with a reversing pushbutton switch.
The user can select either forward rotation (clockwise) or backward rotation (counterclockwise) by simply
pressing the pushbutton.
Refer to the Technical Data and Service Manual for the model indicated below.
3-mode changing and variable lock mechanism for easy
working-angle adjustment of chisels, etc.
This product adopts Hitachi's unique mode selection mechanism: two standard modes of "Rotation +
hammering" and "Rotation" and one additional mode of "Hammering." These modes enables not only light
chiseling work using bull points but also heavy work using cold chisels and cutters such as groove digging
and cornering work, thereby expanding the range of product use.
The user can easily mount a bit in any of 12 angle positions by simply setting the change lever to the
"neutral" position and turning the bit.
Idle striking prevention mechanism with catch-ring method
This product adopts a catch-ring type of idle hammering prevention mechanism.
When the bit tool of the product is detached from an object under no load, air flows in and out through
cylinder air holes to maintain uniform air pressure in the chamber. As a result, the hammering action stops.
In this case, the projection at the tip of the striker fits into the O-ring (A) provided between damper holders
(A) and (B) to prevent the air holes from being blocked by the recoiling striker.
DH 24PC2 / No. E479, DH 24PC3 / No. E489, DH 30PC2 / No. E494
*Based on our own
research
Chiseling amount (kg/30 min.)

-3-
One-push type of bit mounting
This product adopts a one-push quick bit mounting system without needing grip operation.
First, fully insert the bit tool into the front cap hole until it stops, and then turn the bit tool while slightly
pushing the bit tool. When the bit tool catches, push the bit tool there until it stops.
Internal pressure adjustment mechanism
An air passage is provided to connect inside the crankcase to the outside with a felt packing in the air
passage. This passage only allows air (pressure) to pass and suppresses fluctuations in internal pressure.
This stabilizes the hammering action and prevents idle striking and the leakage of grease.
Easy-to-operate and double-molded switch handle and
side handle
The switch handle and side handle both feature a two-layer structure in which the plastic resin molded
base is fully coated with a soft plastic resin. This gives the switch and side handles a soft feeling, and
improves handle operability.
Crank cover
Felt packing
Felt packing (B)
Rubber seal
(
Inside the crankcase
)
A
ir
Air passage
Frontcap Gri
p
Tool

-4-
1. Specifications
Model DH 28PC
Drill bit (Max. dia.): Concrete 28 (1-1/8”)
Steel 13 (1/2”)
Wood 32 (1-1/4”)
Capacity mm
Core bit (Max. dia.): 80 (3 -5/32”)
Power source - AC single phase 50 Hz or 60 Hz
Voltage V110 120 220 230 240
Current A6.9 6.3 3.4 3.3 3.2
Power input W720
Type of motor - AC single-phase commutator motor
Enclosure -
Materials : Nylon resin (Handle (A). (B), tail cover, crank cover)
Polycarbonate resin (Housing)
Aluminum alloy die casting
(Crank case, cylinder case, gear cover)
Colors : Green gray, green, black
Type of switch - Variable trigger switch
Types of handles - D-shaped handle and side handle
Full load rotation rate min-1 0 – 800
Full load impact rate min-1 0 – 4,000
Product* 3.5 (7.7)
Weight
Packed
kg (lbs.)
6.5 (14.3)
Packaging - Plastic case
Standard accessories -
• Plastic case -----------------------------------------------------1
• Side handle------------------------------------------------------1
• Stopper ----------------------------------------------------------1
* Excluding the cord and side handle
SPECIFICATIONS

-5-
2. Optional Accessories
(1) Drilling work for through-hole drilling (rotation + hammering)
Drill bit (SDS plus shank)
D (mm) L1 (mm) L2 (mm) Code No. D (mm) L1 (mm) L2 (mm) Code No.
4.0 303571 12.5 166 100 303592
4.3 303572 12.5 260 200 303607
4.5 303573 12.7 166 100 303593
4.8 303574 12.7 260 200 303608
5.0
110 50
303575 13.0 303594
5.0 160 100 303578 14.0 303595
5.5 303576 14.3
166 100
303596
6.0 110 50 303577 14.3 260 200 303609
6.0 303579 14.5 166 100 303597
6.4 303580 14.5 260 200 303610
6.5 303581 15.0 303598
7.0 303582 16.0 166 100 303599
7.5 303583 16.0 260 200 303611
8.0
160 100
303584 16.5 303600
8.5 160 100 303585 17.0 166 100 303601
9.0 303586 17.0 260 200 308485
9.5 303587 17.5 166 100 303602
10.0
160 100
303588 17.5 260 200 303612
10.0 260 200 303604 18.0 166 100 303603
10.5 160 100 303589 19.0 260 200 303613
10.5 260 200 303605 20.0 303614
11.0 160 100 303590 22.0 303615
12.0 166 100 303591 24.0
250 200
308486
12.0 260 200 303606 25.0 450 384 303616
L2
L1
D

-6-
(2) Drilling anchor holes (rotation + hammering)
Drill bit (taper shank)
(a) Drill bit (taper shank) (b) Taper shank adapter (c) Cotter
(SDS-plus shank)
(a) Drill bit (Taper shank) (b) Taper shank adapter (c) Cotter
Outer dia. (mm) Code No. Type Code No. Code No.
11.0 (7/16")
12.3 (1/2")
12.7 (1/2")
14.3 (9/16")
14.5 (9/16")
17.5 (11/16")
944460
944461
993038
944462
944500
944463
Morse taper
No. 1 303617
21.5 (7/8") 944464 Morse taper
No. 2 303618
944477
Part name Code No.
A-taper 303619
B-taper 303620
A taper shank adapter (A-taper or B-taper) is provided
as an optional accessory, but without the drill bit.
(3) Anchor setting (hammering only)
Anchor setting bar
• Anchor setting bar to permit anchor setting operation with the rotary hammer
Anchor setting adapter (SDS-plus shank)
Part name Overall
length
Code
No. Part name Overall length
Code
No.
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
260
260
160
260
302976
302975
303621
302974
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
260
260
160
260
302979
302978
303622
302977
Internal cone type External cone type
• Anchor setting bar for manual anchor setting
Anchor setting adapter
Part name Code No. Part name Code No.
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
971794
971795
971796
971797
971798
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
971799
971800
971801
971802
971803
Internal cone type External cone type
+
+

-7-
(4) Large hole boring (rotation + hammering)
• Center pin, core bit, core bit shank and guide plate
(a) Guide plate (b) Center pin (c) Core bit (d) Core bit shank
(SDS-plus shank)
(a) Guide plate
Core bit (outer diameter ) (mm) Code No. Core bit (outer diameter ) (mm) Code No.
32 (1-1/4") 982686 50 (2") 982690
35 (1-3/8") 982687 65 (2-9/16") 982691
38 (1-1/2") 982688 80 (3-5/32") 982692
45 (1-3/4") 982689
(b) Center pin (Do not use bits with outer diameters of 25 mm (1") and 29 mm (1-1/8"))
Part name Code No.
Center pin (A) Core bit (outer diameter) 32, 35, 38 mm (1-1/4", 1-3/8", 1-1/2") 982684
Center pin (B) Core bit (outer diameter) 45, 50, 65, 80 mm (1-3/4", 2", 2-9/16", 3-5/32") 982685
(c) Core bit with guide plate
(The guide plate is not supplied with 25 mm (1") and 29 mm (1-1/8") outer diameter core bits.)
Outer diameter (mm) Code No. Outer diameter (mm) Code No.
25 (1") 982672 45 (1-3/4") 982677
29 (1-1/8") 982673 50 (2") 982678
32 (1-1/4") 982674 65 (2-9/16") 982679
35 (1-3/8") 982675 80 (3-5/32") 982680
38 (1-1/2") 982676
(d) Core bit shank (SDS-plus shank)
Part name Overall length Code No.
105 mm (4-1/8") 303625
Core bit shank (A) Core bit (outer diameter) 25 --38 mm
(1" --1-1/2") 300 mm (12") 303626
Core bit shank (B) Core bit (outer diameter) 45 --80 mm
(1-3/4" --3-5/32") 300 mm (12") 303627
(5) Bolt placing operation with chemical anchor (rotation + hammering)
(Commercially available Chemical anchor adapter
standard socket) (SDS-plus shank)
Part name Code No.
12.7 mm (1/2") Chemical anchor adapter 303044
19.0 mm (3/4") Chemical anchor adapter 303045
+
++
+