HP 6730b Service Manual

							Grounding guidelines
Electrostatic discharge damage
Electronic components are sensitive to electrostatic discharge (ESD). Circuitry design and structure
determine the degree of sensitivity. Networks built into many integrated circuits provide some protection,
but in many cases, ESD contains enough power to alter device parameters or melt silicon junctions.
A discharge of static electricity from a finger or other conductor can destroy static-sensitive devices or
microcircuitry. Even if the spark is neither felt nor heard, damage may have occurred.
An electronic device exposed to ESD may not be affected at all and can work perfectly throughout a
normal cycle. Or the device may function normally for a while, then degrade in the internal layers,
reducing its life expectancy.
CAUTION:To prevent damage to the computer when you are removing or installing internal
components, observe these precautions:
Keep components in their electrostatic-safe containers until you are ready to install them.
Before touching an electronic component, discharge static electricity by using the guidelines described
in this section.
Avoid touching pins, leads, and circuitry. Handle electronic components as little as possible.
If you remove a component, place it in an electrostatic-safe container.
The following table shows how humidity affects the electrostatic voltage levels generated by different
activities.
CAUTION:A product can be degraded by as little as 700 V.
Typical electrostatic voltage levels
 
Relative humidity
Event10%40%55%
Walking across carpet35,000 V15,000 V7,500 V
Walking across vinyl floor12,000 V5,000 V3,000 V
Motions of bench worker6,000 V800 V400 V
Removing DIPS from plastic tube2,000 V700 V400 V
Removing DIPS from vinyl tray11,500 V4,000 V2,000 V
Removing DIPS from Styrofoam14,500 V5,000 V3,500 V
Removing bubble pack from PCB26,500 V20,000 V7,000 V
Packing PCBs in foam-lined box 21,000 V 11,000 V 5,000 V
Preliminary replacement requirements 41 
						

							Packaging and transporting guidelines
Follow these grounding guidelines when packaging and transporting equipment:
●To avoid hand contact, transport products in static-safe tubes, bags, or boxes.
●Protect ESD-sensitive parts and assemblies with conductive or approved containers or packaging.
●Keep ESD-sensitive parts in their containers until the parts arrive at static-free workstations.
●Place items on a grounded surface before removing items from their containers.
●Always be properly grounded when touching a component or assembly.
●Store reusable ESD-sensitive parts from assemblies in protective packaging or nonconductive
foam.
●Use transporters and conveyors made of antistatic belts and roller bushings. Be sure that
mechanized equipment used for moving materials is wired to ground and that proper materials are
selected to avoid static charging. When grounding is not possible, use an ionizer to dissipate
electric charges.
Workstation guidelines
Follow these grounding workstation guidelines:
●Cover the workstation with approved static-shielding material.
●Use a wrist strap connected to a properly grounded work surface and use properly grounded tools
and equipment.
●Use conductive field service tools, such as cutters, screwdrivers, and vacuums.
●When fixtures must directly contact dissipative surfaces, use fixtures made only of static-safe
materials.
●Keep the work area free of nonconductive materials, such as ordinary plastic assembly aids and
Styrofoam.
●Handle ESD-sensitive components, parts, and assemblies by the case or PCM laminate. Handle
these items only at static-free workstations.
●Avoid contact with pins, leads, or circuitry.
●Turn off power and input signals before inserting or removing connectors or test equipment.
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							Equipment guidelines
Grounding equipment must include either a wrist strap or a foot strap at a grounded workstation.
●When seated, wear a wrist strap connected to a grounded system. Wrist straps are flexible straps
with a minimum of one megohm ±10% resistance in the ground cords. To provide proper ground,
wear a strap snugly against the skin at all times. On grounded mats with banana-plug connectors,
use alligator clips to connect a wrist strap.
●When standing, use foot straps and a grounded floor mat. Foot straps (heel, toe, or boot straps)
can be used at standing workstations and are compatible with most types of shoes or boots. On
conductive floors or dissipative floor mats, use foot straps on both feet with a minimum of one
megohm resistance between the operator and ground. To be effective, the conductive strips must
be worn in contact with the skin.
The following grounding equipment is recommended to prevent electrostatic damage:
●Antistatic tape
●Antistatic smocks, aprons, and sleeve protectors
●Conductive bins and other assembly or soldering aids
●Nonconductive foam
●Conductive tabletop workstations with ground cords of one megohm resistance
●Static-dissipative tables or floor mats with hard ties to the ground
●Field service kits
●Static awareness labels
●Material-handling packages
●Nonconductive plastic bags, tubes, or boxes
●Metal tote boxes
●Electrostatic voltage levels and protective materials
The following table lists the shielding protection provided by antistatic bags and floor mats.
MaterialUseVoltage protection level
Antistatic plasticBags1,500 V
Carbon-loaded plasticFloor mats7,500 V
Metallized laminate Floor mats 5,000 V
Preliminary replacement requirements 43 
						

							Unknown user password
If the computer you are servicing has an unknown user password, follow these steps to clear the
password:
NOTE:These steps also clear CMOS.
1.Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn the
computer on, and then shut it down through the operating system.
2.Disconnect all external devices connected to the computer.
3.Disconnect the power from the computer by first unplugging the power cord from the AC outlet and
then unplugging the AC adapter from the computer.
4.Remove the battery (see 
Battery on page 47).
5.Remove the real-time clock (RTC) battery (see 
RTC battery on page 55).
6.Wait approximately 5 minutes.
7.Replace the RTC battery and reassemble the computer.
8.Connect AC power to the computer. Do not reinsert any batteries at this time.
9.Turn on the computer.
All passwords and all CMOS settings have been cleared.
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							Component replacement procedures
This chapter provides removal and replacement procedures.
There are as many as 96 screws and screw locks, in 16 different sizes, that must be removed, replaced,
or loosened when servicing the computer. Make special note of each screw and screw lock size and
location during removal and replacement.
Service tag
The service tag, affixed to the bottom of the computer, provides information that may be needed when
troubleshooting system problems. The service tag provides the following information:
(1) Product name: This is the product name affixed to the front of the computer.
(2) Serial number (s/n): This is an alphanumeric identifier that is unique to each product.
(3) Part number/Product number (p/n): This number provides specific information about the products
hardware components. The part number helps a service technician to determine what components and
parts are needed.
(4) Model description: This is the number used to locate documents, drivers, and support for the
computer.
(5) Warranty period: Describes the duration of the warranty period for the computer.
Component replacement procedures 45 
						

							Computer feet
The computer feet are adhesive-backed rubber pads. The feet are included in the Rubber Kit, spare
part number 487145-001. There are 8 rubber feet that attach to the base enclosure in the locations
illustrated below.
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							Battery
DescriptionSpare part number
6-cell, 55-Wh battery486296-001
6-cell, 47-Wh battery486295-001
Before disassembling the computer, follow these steps:
1.Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn the
computer on, and then shut it down through the operating system.
2.Disconnect all external devices connected to the computer.
3.Disconnect the power from the computer by first unplugging the power cord from the AC outlet and
then unplugging the AC adapter from the computer.
Remove the battery:
1.Turn the computer upside down on a flat surface, with the battery bay toward you.
2.Slide the battery release latch (1) to release the battery.
3.Remove the battery (2) from the computer.
Install the battery by inserting it into the battery bay until you hear a click.
Component replacement procedures 47 
						

							SIM
NOTE:This section applies only to computer models with WWAN capability. If there is a SIM inserted
in the SIM slot, it should be removed before disassembling the computer. Be sure the SIM is reinserted
in the SIM slot after reassembling the computer.
Before removing the SIM, follow these steps:
1.Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn the
computer on, and then shut it down through the operating system.
2.Disconnect all external devices connected to the computer.
3.Disconnect the power from the computer by first unplugging the power cord from the AC outlet and
then unplugging the AC Adapter from the computer.
4.Remove the battery (see 
Battery on page 47).
Remove the SIM:
1.Press in on the SIM (1). (The module is partially ejected from the SIM slot.)
2.Remove the SIM (2) from the SIM slot.
Reverse this procedure to install the SIM.
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							Display inverter
DescriptionSpare part number
For use only with HP Compaq 6735b computer models495086-001
For use only with HP Compaq 6730b computer models 486773-001
Before removing the display inverter, follow these steps:
1.Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn the
computer on, and then shut it down through the operating system.
2.Disconnect all external devices connected to the computer.
3.Disconnect the power from the computer by first unplugging the power cord from the AC outlet and
then unplugging the AC Adapter from the computer.
4.Remove the battery (see 
Battery on page 47).
Remove the display inverter:
1.Turn the computer right-side up, with the front toward you.
2.Open the computer as far as it will open.
3.Remove the two rubber screw covers (1) on the bottom edge of the display bezel. The rubber screw
covers are available in the Display Rubber Kit, spare part number 486775-001.
4.Remove the two Torx8 T8M2.5×6.0 screws (2) that secure the bottom edge of the display bezel to
the display enclosure.
5.Flex the hinge cover areas (1) and the bottom edge (2) of the display bezel until the bezel
disengages from the display enclosure.
Component replacement procedures 49 
						

							6.Release the bottom edge of the display bezel (3) from the display assembly.
7.Release the inverter (1) from the display enclosure as far as the display panel cable and backlight
cable allow.
8.Disconnect the display panel cable (2) and the backlight cable (3) from the display inverter.
9.Remove the display inverter.
Reverse this procedure to install the display inverter.
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