Introduction
1
General
Siemens Energy & Automation portable test set type PTS-4
is designed for testing the static overcurrent tripping systems
used on the LA and RL line of low voltage power circuit
breakers. It provides a means of testing the magnetic tripping
actuator as well as the static trip device. The portable test set,
using power from an ordinary 120 volt convenience outlet,
can provide circuit breaker testing equivalent to much more
expensive and cumbersome primary current testing.
This instruction book provides the information necessary to
test all models of static trip systems produced by Allis-
Chalmers, Siemens-Allis or Siemens Energy & Automation
from the original first generation models to the latest versions
of STATIC TRIP 111 and LIMITRIP. First generation systems
are discussed in more detail in instruction book 18X4392,
STATIC TRIP II in books 18X4827, 18X4433 and SG -3098.
LlMITRIP is covered in book 18X10107 and SG-3108. STATIC
TRIP 111 in SG-3118.
Factory calibration of the trip devices is done with sinusoidal
current from a closely regulated supply and with high quality
instruments that are frequently recalibrated. These condi-
tions cannot be duplicated in a portable tester. In particular,
120 volt line variations during testing may affect results.
Therefore, minor discrepancies between factory calibration
and test set readings can be safely disregarded.
The test set itself is quite accurate and can be used to
calibrate additional pickup and short time delay values on the
trip devices if a sufficiently stable 120 volt line is available. The
voltage can be anywhere between 105 and 125 volts, but the
value should not vary by more than + 1.5% during testing.
Static Trip III Calibration Marks
Each static trip of the first generation or STATIC TRIP II type,
is individually calibrated during factory test. Because the
location of the calibration points varies from device to device,
it is not possible to preprint the identification letters adjacent
to the marks. To identify a letter or label with its calibration
dot, start from the reference dot (see “Restoring Lost Calibra-
tion”) and count the calibration dots around the dial in the
direction (clockwise or counterclockwise) indicated by the
sequence of the letters or labels. For example, the “C” LONG
TIME PICKUP dot is the third calibration dot counted clock-
wise from the reference dot. On STATIC TRIP II the direction
of counting is also the direction indicated by the “increase”
arrow.
Restoring Lost Calibration
The pointer of each knob when turned counterclockwise
against its stop should line up with its reference dot. (Refer-
ence dots are black on STATIC TRIP 11 and red on first
generation devices). If the pointer does not line up with its
reference dot, the knob has turned on its shaft. To restore the
knob to its proper location on the shaft, loosen the set screw
in the knob, make sure the shaft is turned fully counterclock-
wise, align the pointer with the reference dot and tighten the
set screw. Recheck that the pointer now aligns with the
reference dot when it is rotated against its stop. On first
generation devices the knob locks must be loosened in order
that the shaft can be rotated.
LIMITRIP and STATIC TRIP III devices have no calibration
marks since the settings of the device are made with
switches. rather than potentiometers.
