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Elevator Pretest Procedures
A. Traction or Hydraulic Elevators:
1. These guidelines are presented in an effort to prevent waste of time
and money in the final testing of elevators. This procedure is intended
to determine if an elevator is ready for final inspection. Of all the
deficiencies usually found during inspection, only a few result in
aborting the test.
2. CAUTION: Testing a newly installed elevator can be quite dangerous.
Without previous experience in testing elevators, the chance of serious
injury increases. WE STRONGLY URGE YOU TO STAY OUT OF THE HOISTWAY. Any
observations or measurements described in this procedure can be accomplished
from outside the hoistway, with the assistance of the elevator mechanic.
Have the elevator mechanic verify that the safety circuit is operating
properly. The hoistway door interlocks, car gate switch, final runby limit
switches, all stop switches, and the car top emergency exit switch when
open, shall stop the elevator and prevent it from running until the switches
are closed.
3. Observe all hall lanterns, hall and car position indicators, and hall
push buttons for proper operation. Check for car floor leveling to be
within 1/4 inch at empty and full capacity loads. All elevators must
have a working car communications system. The system shall be an ADA
hands free telephone system. Elevators must also have Phase 1 and Phase
2 fire service and smoke detector systems. Communication and fire
services are code items and shall function as per National Elevator
Code ASME A17.1. Elevators cannot be accepted with code violations.
4. When testing in the machine room, be especially aware of rotating
equipment such as the hydraulic pump and pump motor. This belt drive
combination can start at any time for reasons other than floor to
floor travel. On a traction elevator, the hazard is the drive sheave
and cables. Constant awareness is needed when a traction elevator is
being tested for correct speeds. Further hazards are the obvious dangers
of tripping, falling, and electrical shock.
B. Hydraulic Elevators:
1. Through the bottom hoistway door observe that the automatic shutoff
valve has been installed as close as possible to the head of the jack
assembly. Do not use victaulic fittings between the jack and the shutoff
valve.
2. Verify that all piping and fittings are of specified size before
further testing. (Entire system rated for twice the working pressure.)
This verification should be provided to you by the elevator contractor.
3. To test the automatic shutoff valve, place rated capacity on the
elevator. Request a terminal-to-terminal run, after which you direct
the elevator mechanic to cause the automatic shutoff valve to be
activated. This can usually be observed through the bottom hoistway
door when the door lock is bypassed by the elevator mechanic. Activation
shall be caused by either overloading or overspeeding, or a combination
of both. Under no circumstance is the mechanic to enter the pit from the
start of the terminal runs until the completion of the test. After
successful activation of the automatic shutoff valve, have the mechanic
run the elevator up to reset the valve. Remove the overloading or
overspeeding condition and make three terminal-to-terminal runs again.
BE SURE TO REMIND THE MECHANIC TO REMOVE ANY CIRCUIT BYPASS DEVICE USED
DURING THE TEST. It should be emphasized that NO ONE IS TO ENTER THE PIT
FROM THE LOADING OF THE WEIGHTS TO THE COMPLETION OF THE TEST. Adjustment
of the automatic shutoff valve for any reason during the test nullifies
the test, and it must be started again.
4. Amperage of the pump motor shall be checked with an ammeter or amprobe,
preferably in the controller. The reading should be taken on up runs with
full capacity on the elevator. A reading of more than 10% of the motor's
own amperage rating, as stamped on the data tag, indicates that the motor
size is not sufficient and should be replaced.
5. A point of information regarding the pump motor size. Experience has
shown that a horsepower rating of between 40 and 60 has been needed for
successful operation of our standard elevators rated at 4,000 or 5,000
lbs. capacity. Rarely, if at all, has a 30 horsepower motor proved to
be adequate.
6. To test the pressure, first determine that the gauge is placed in
the machine room where it is reading pump pressure to the jack assembly.
With full capacity on the elevator, the pressure must not exceed 500 PSI
on an up run.
7. Observe that all specified devices, such as muffler, shutoff valves
and gate valves are installed at the time the unit is tested. Any
additions made to the hydraulic pipe run usually causes an increase to
both the working pressure and pump motor amperage. If any changes have
to be made to the pipe run, the amperage and pressure readings should not
be recorded until changes are completed.
8. Conduct a one-hour performance test. With rated capacity on the car,
take temperature readings of the pump motor, the hydraulic oil and the
machine room. Start the one-hour test. The doors shall operate at every
stop at each floor. Floor accuracy of plus or minus 1/4 inch shall be
observed at the start of the test, as well as the completion. If the
elevator is unable to run for one hour without repairs or adjustments,
then it is not ready for final inspection. Reason dictates that a
one-time shutdown, with a simple solution, should not abort this pretest.
However, repeated shutdown of any nature indicates that the elevator is
not ready for final testing.
9. At the end of the one-hour performance test, the elevator should still
be stopping level in both directions, without releveling operations.
Obvious changes in floor levels or harshness of starting or stopping
indicate major problems. Also, temperature rise in excess of nameplate
ratings indicates that the final test should be aborted.
C. Electric Traction Elevators:
1. Check the amperage in the controller with an ammeter or amprobe.
The readings shall be taken in both directions with empty car and full
load. Readings of more than 5% over data tag number located on
SCR DRIVE, the data tag located on the machine, indicates
possible motor problems and is not acceptable.
2. Check the car safeties. After taching the speed governor or being
assured that it has been tached and properly set, request a demonstration
of the elevator safeties. This may be done with an empty car. The elevator
shall be run at inspection speed in the down direction to the point where
the speed governor, when manually tripped will activate the car safeties,
and the car safeties will wedge themselves on the guide rails. The governor
shall be activated by the elevator mechanic.
3. Conduct a one-hour performance test. After loading the elevator to
capacity, record the machine room temperature, and the temperature of
the hoist motor. Run the one-hour performance test in the manner similar
to the description under hydraulic elevators. At completion, look for
noticeable changes in smoothness of starting and stopping, and accuracy
of the floor stops. Check for "roll back" when brake is lifted. Failure
in these areas and/or repeated shutdowns indicates the elevator is not
ready for final inspection.
4. To conduct the buffer tests, have the car and counterweights strike
the buffers with an empty load on the car. These tests are to be done
at inspection speed. Following each test, observe that the buffer has
returned to the original height within 90 seconds. Also check that
excessive oil leakage did not occur. A slight spray is acceptable.
5. During the buffer test, excessive oil leakage would be indicated by
oil sprayed on pit walls and floor, or seen dripping from elevator car
frame following the striking of the buffers. Either condition would
require necessary repairs or replacement of buffers before a final test
should be scheduled.
D. Other Recommendations:
1. Any parts or items that have to be replaced because of failure during
pretesting, that would change the hydraulic or electrical system, would
have to be pretested before the final testing is scheduled.
2. For assistance, contact the Consulting Support Service (183A), Bill
Haupt @ 202-565-9371.
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