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Each new instrument is furnished with an operator’s manual. The manual
contains a description of the instrument, specifications of its various
components and capabilities, and applications. The manual also contains basic
instructions for use of the instrument and describes recommended servicing
and adjusting methods. The operator’s manual should be kept with the
instrument at all times. Each operator should thoroughly study the manual
prior to use of he instrument, particularly whenever prescribed field adjustments
are to be made. If the manual is lost, stolen, or damaged beyond use, a
replacement copy should be obtained as soon as practicable.
The
following general principles of care and servicing should be applied as a
routine matter for all survey equipment and supplies.
§ All equipment and tools should be
kept as clean and dry as practicable, particularly if they are to be
transported or stored for any length of time.
§ Wooden surfaces should be wiped
clean of caked mud or moisture prior to returning the equipment to the
vehicle. The original painted or varnished surfaces should be repaired as
often as needed to keep moisture from entering the wood.
§ Metal surfaces should be cleaned
and wiped as dry as practicable. A coat of light oil should be applied to
tapes and the metal parts of tools to prevent rusting during storage. Excess
oil should be wiped off.
Routine Care
of Surveying Instruments.
§ Before making the first set up of
the day, visually inspect the instrument for cracks, bumps, and dents. Check
the machined surfaces and the polished faces of the lenses and mirrors. Try
the clamps and motions for smooth operation (absence of binding or gritty
sound).
§ Frequently clean the instrument
externally. Any accumulation of dirt and dust can scratch the machined or polished
surface and cause friction or sticking in the motions.
§ Dirt and dust should be removed
only with a clean soft cloth or with a camel hair brush.
§ Non-optical parts may be cleaned
with a soft cloth or clean chamois.
§ Clean the external surfaces of
lenses with a fine lens brush and , if necessary, use a dry lens tissue. Do
not use silicon treated tissues, as they can damage the coated optics. It is
permissible to breath on the lens before wiping it, but liquids, such as oil,
benzene, water, etc., should never be used for cleaning purposes. DO NOT loosens or attempt to clean the
internal surface of any lens.
§ Cover an instrument whenever it
is uncased and not being used for any length of time, particularly if there
is dust or moisture in the air. After an instrument has been used in damp or
extremely cold situation, special precautions must be taken to prevent condensation
of moisture inside of the instrument. When working with the instrument in
cold weather, it should be left in the carrying case in the vehicle
overnight. If stored in a heated room overnight, the instrument must be
removed from the carrying case. If the instrument is wet or frost covered it
should be remove it from its case, and leave it at room temperature to dry
out.
3. Care in Transporting Surveying Equipment.
Vehicular
Transport
§ The major damage to equipment and
tools occurs when they are being placed into or taken out of the survey
vehicle. Other damage occurs during transport, when equipments is jostled
against other tools or equipment. Compartments (lined with carpeting, when possible)
should be provided to keep equipment and supplies separated. This not only
keeps the equipment from being damaged, it facilitates finding such items
more rapidly. Heavier items should be carried in the lower parts of vehicles
and they should never be in direct contact with other tools or equipment
below them.
§ The care, organization, and
general housekeeping of a vehicle are good indications of the attitude of the
entire survey crew. Keep passenger compartments free of unnecessary clutter
and equipment. Any equipment or material carried in the passenger compartment
should be firmly secured.
§ Transport and store instrument in
positions that are consistent with the carrying case design. Many instrument
cases indicate the position in which they should be transported. Treat
optical targets, prisms, and staffs with the same consideration.
§ Transport the instruments in
their carrying cases placed in a compartment cushioned with firm poly foam or
similar material to protect them from jolting or excessive vibrations.
§ Remember, loose equipment, out of
place tools, and general clutter not only contributes to damage of the items,
they also waste crew time in locating them and are a safety hazard.
Casing
and Uncasing
Before
removing an instrument, study the way it is placed and secured in the case.
The instrument must be replaced in the same position when returned to the
case. In removing the instrument from the case, carefully grip it with both
hands, but do not grip the vertical circle standard or where pressure will be
exerted on tubular or circular level vials.
Field
Transport of Surveying Instrument
Do
not “shoulder” or carry a tripod mounted theodolite or electronic
distance measuring equipment (EDM). These instruments should always be
removed from the tripod and secured in their carrying cases when moved.
These
precautions are necessary because the center spindle (center spigot or
standing axis) of a theodolite is hollow and relatively short. When carried
horizontally while on the tripod, the alidade’s weight is an excessive load
for the hollow centerpiece to bear. Instrument damage can result if the above
precautions are ignored. Also, the instrument fastener can break, causing the
theodolite to fall.
4. Care During
Instrument Setups
- Whenever possible, select instrument stations where
operation is not dangerous to the instrument operator, the crew, or the
instrument. Select stable ground for the tripod feet. Do not set an
instrument closely in front of, or behind, a vehicle or equipment which
is likely to move. Take a safe route to all setups.
- At the site, firmly plant the tripod with its legs
widespread. Push along the legs, not vertically, downward. On smooth
surfaces, use some type of tripod leg restrainer to keep the legs from
sliding outward.
- Always have the tripod firmly set over the point
before removing the instrument from its carrying case. Immediately
secure the instrument to the tripod with the instrument fastener.
- Never leave an instrument or its tribrach on the
tripod without securing either to the tripod. Moderate pressure on the
fastener screw is sufficient. Excessive tightening causes undue pressure
on the foot screws and on the tribrach spring plate. Make sure the
tribrach clamp is in the lock position.
5. Adjustments
of Surveying Instruments.
Field
Adjustments
The
crew leader should develop a set of test procedure to be used frequently for
elimination of gross errors. Such tests should include a check of items such
as the level, optical plummet, and tripod. In the field, adjustments should
only be made when the instrument results are poor or require excessive
manipulation.
Normally,
each instrument should be periodically checked at a facility where the best
conditions for testing are possible. Only the adjustments described in the
manual for the instrument should be made in the field or shop. Do not “field
strip” (dismantle) instruments.
Major
Adjustments
When
an instrument has been damaged or otherwise requires major adjustments, it
will need to be sent to an authorized repair shop. The instrument should be
accompanied by a written statement indicating the types of repairs needed. In
the case of electronic devices, the request should describe conditions under
which the instrument does not function properly, i.e. coldness, dampness,
etc. if a “loaner” is needed, this should also be indicated.
6. Care of
Tools
- Improperly maintained tools can be a source of
annoyance, as well as being a safety hazard. Each employee is
responsible for keeping his or her tools and equipment in good
condition. To prevent loss of small equipment and tools, avoid laying
them on the ground, on vehicles, or on equipment which might be moved.
When not in use, carry them in scabbards and pouches.
- Repair or replace any driving tool that is burred or
fractured on any part of the striking or driving face. Many surveyors
have been injured by the “shrapnel” effect from gads and sledges which
had ragged edges. The same is true for “bull points” or other tool which
are driven.
- Crooked or warped handles can cause injury as well as
mistitling and damage to the tool. Promptly replace such handles and
those that are cracked or broken. Handles should be firmly secured in
all cutting and driving tools.
7. Care of Theodolites and Total Stations
§ Although the instruments are
ruggedly built, careless or rough use and unnecessary exposure to the
elements can seriously damage them. If handled reasonably, they will provide
consistently good result with a minimum of downtime for repair or adjustment.
Some general guidelines for the care of instruments are:
§ Lifting – instruments should be removed
from the case with both hands, gripping the micrometer knob standard and base
on the older instruments. Newer instruments are equipped with a carrying
handle; the other hand should support the base. One hand should continually
support the instrument until the tribrach lock is engaged and the tripod
fixing screw secured.
§ Carrying Tripod – In most cases, the instrument
should be removed and re-cased for transportation to a new point. If the
point is nearby, the instrument should be carried in the vertical position
(tripod legs pointing straight down). An instrument should never be
“shouldered” or carried horizontally.
§ Adjusting collimation – The collimation error of
theodolites and total stations is determined by following the procedure
outlined in the users’ manual. If the collimation error is found to be
consistently in excess of ten seconds on the horizontal and twenty seconds on
the vertical, the instrument should be adjusted. The collimation adjustment
should be made in the field only by a specially trained individual. Otherwise,
the instrument should be returned to an authorized repair shop.
8. Care of EDM
Devices
§ EDMs are designed, contracted and
tested to withstand normal field conditions. They are however, precision
instruments and should be handled with the same degree of care required for
other types of precision survey equipment.
§ Secure EDM in vehicles in padded
compartments with substantial the downs so movement and jarring are
minimized. Cushion with firm polyfoam or similar material. Do not use soft
foam rubber. The instruments should be stored and transported in the position
indicated on the case.
§ Required maintenance of most EDMs
is minimal. However, protection from the elements and routine external
cleaning is necessary.
§ NEVER point an EDM directly at the sun.
The focused rays of the sun can damage sensitive internal parts.
§ Protect EDMs from excessive heat.
Heat can cause erratic readings and deterioration of components. Do not leave
instruments in closed vehicles that are parked in the sun. Avoid rapid
changing temperature, particularly from extreme cold to warm, which can cause
condensation in the internal parts of the instruments. Condensation can
normally be avoided by leaving the instrument in its carrying case for at
least 10 minutes and then opening the case to allow any trapped moisture to
evaporate. An instrument taken from a warm office or vehicle to an extremely
cold operating environment may require some time to adjust itself. The same
type of precautions should be taken to let the instrument cool off slowly.
§ Although EDM instruments are
water resistant and well shielded, keep them as dry as practicable. The case
should be opened and the instrument allowed to dry in a warm dry room when
not in sue.
§ Frequent partial discharge and
charge of batteries could cause the battery to lose its ability to hold
power. Periodically, batteries should be discharged completely and then
recharged overnight, or for the specified charge time. Effective usage of
batteries will also decrease at low temperatures. An EDM in the tracking mode
position will discharge the battery will also decrease at low temperatures.
An EDM in the tracking mode position will discharge the battery quite
rapidly, so it is important to be able to charge batteries to their maximum
capacity. In general, one should follow the user’s manual instructions on how
to maintain the batteries for top performance. If the batteries still fail to
hold power, they should be re-celled or replaced.
9. Care of
Tapes
§ Routine care extends tape life.
The following are basic guidelines for the care of tapes.
§ Do not place a tape where it can
be stepped on or run over, unless the tape is flat, taut, and fully supported
on a smooth surface. Keep the tape straight when is used. When pulling a
slack tape, a loop can develop into a kink and easily break the tape. Avoid
pulling a tape around poles or other object, as a hard pull can stretch or
break the tape.
§ Do not wind tapes overly tight on
their reels, as it can cause unwanted stresses and lead to stretching of the
tape.
§ After the day’s work, clean tapes
that are soiled. In wet weather, dry before storing. Clean rusty tapes with
fine steel wool and cleaning solvent or kerosene. Use soap and water when
tape is dirty or muddy. To prevent rust after cleaning, oil lightly and then
dry the tape.
§ Avoid storing in damp places.
10. Care of Tribrachs
Tribrachs
are an integral part of the precision equipment and should be handled
according. They should be transported in separate compartments or other
containers to prevent damage to the base surface, bulls eye level, and optical
plummet eye piece. Over tightening of the tripod fastener screw can put undue
pressure on the leveling plate.
11. Care of
Tripods
A
stable tripod is required for precision in measuring angles. A tripod should
not have any loose joints or parts which might cause instability. Some
suggestions for proper tripod care are:
- Maintain firm snugness in all metal fittings, but
never tighten them to the point where they will unduly compress or
injure the wood, strip threads or twist off bolts or screws.
- Tighten leg hinges only enough for each leg to just
sustain its own weight when legs are spread out in their normal working
position.
- Keep metal tripod shoes tight and free of dirt.
- Keep wooden parts of tripods well painted or varnished
to reduce moisture absorption and swelling or drying out and shrinking.
- Replace top caps on tripods when not in use.
12. Care of
Levels
Review
the previously stated guidelines for the care of instruments. These
guidelines are also generally true for the proper care of pendulum levels. Additional
guidelines are.
- Do not spin or bounce pendulum levels, as such
movement can damage the compensator.
- Protect the level from dust. Dust or foreign matter
inside the scope can cause the compensator’s damping device to hang-up.
- Frequently check the adjustment of the bull’s eye
bubble. Adjust the bull’s eye to the center, not almost to the center.
Make certain it is adjusted along the line of sight and transversely as
well. Proper adjustment reduces the possibility of compensator hang up.
- To check for compensator hang up, slightly tap the
telescope with a pencil or operate the fine movement screw jerkily to
and fro. If the instrument has a push button release, use it, if the
compensator is malfunctioning, send the instrument to an approved repair
service for servicing. Do not attempt compensator repair in the field.
13. Care of
Leveling Rods.
Leveling
rods should be maintained and checked as any other precision equipment.
Accurate leveling is as dependent on the condition of the rods as on the
condition of the levels. Reserve an old rod for rough work, such as measuring
sewer inverts, mud levels, etc. The care requirements common to all types of
rods are:-
- Protect from moisture, dirt dust and abrasion
- Clean graduated faces with a damp cloth and wipe dry.
Touch graduated faces only when necessary and avoid laying the rod where
the graduated face will come into contact with other tools, objects,
matter, or materials where damage might result.
- Do not abuse a rod by placing it where it might fall,
throwing, and dropping, dragging, or using it as a vaulting pole.
- Keep the metal shoe clean and avoid using it to scrape
foreign matter off a bench or other survey points.
- If possible, leave a wet rod uncovered, unclosed, and
extended until it is thoroughly dry.
- Store rods, either vertically (not leaning) or
horizontally with at least three point support, in a dry place and in
their protective cases.
- Periodically check all screws and hardware for
snugness and operation
- Periodically check accuracy by extending the rod to
its full length and checking its scale with an accurate tape. This
should be done at the beginning of control level surveys. If the rod
indicates a tendency to be “off”, it should be checked each time it is
extended.
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