7MN16004
• When the CST controller is operated in a “noise-polluted”
industrial environment, special consideration should be given
to possible electrical interference. The following reduces the
eect of electrical interference:
• Proper equipment grounding
• Proper routing of wiring
• Proper suppression added to noise generating devices
• Potential noise generators include inductive loads, such as
relays, solenoids, and motor starters when operated by “hard
contacts” like push buttons or selector switches. Suppression
may be necessary when such loads are connected as output
devices or when connected to the same supply line that
powers the controller. Lack of surge suppression on inductive
loads may contribute to processor faults and sporadic
operation.
• Use of a suppression device on outputs used to control
inductive devices is recommended such as:
• Relays
• Motor starters
• Solenoids
• Switching inductive loads without surge suppression can
signicantly reduce the lifetime of relay contacts. Suitable
surge suppression methods for inductive AC load devices
include a varistor, a RC network, or a surge suppressor. These
components must be appropriately rated to suppress the
switching transient characteristic of the particular inductive
device. The suppression device should be located as close
as possible to the load device.
Grounding: Grounding helps limit the eects of electrical noise
due to electromagnetic interference (EMI). The equipment
grounding copper bar/lug provides the ground path for the CST
enclosure. 10-1 4AWG ground conductor wire should be used
and terminate on the ground lug.
Shielding: All the CST instrument analog signal cables to
and from the CST should be shielded at one end only. It is
recommended that the shield should be terminated on the
copper bar provided inside the CST controller enclosure.
The other end, towards the eld transducer, should be taped/
insulated and not connected to any ground.
CAUTION: The CST enclosure and other control devices
must be grounded properly. All applicable codes and
ordinances must be observed when wiring the control
system.
CAUTION: The belt piece should be thick and bent to
produce sucient “coil spring” action. If the belt support
is “rigid,” it can cause failure in the bearings of the encoder
shaft and can transmit erratic signals to the controller.
CAUTION: The shielded cable must be grounded properly
inside the CST controller. DO NOT GROUND THE SHIELD
INSIDE THE JUNCTION BOX. All National Electric Code and
applicable local codes and ordinances must be observed
when wiring the system.
Output Shaft Speed Sensor
An electromagnetic sensor, mounted on the "TAC Wheel" cover
measures the output shaft speed of the CST. The speed probe is
adjusted for the air-gap between the tooth wheel and the sensor
tip; however, it is likely that during installation and/or during
commissioning, the adjusted gap will be disturbed. If the speed
signal is lost, the following corrective action may be taken:
1. Loosen the lock-nut and turn the speed probe clockwise until
it touches the tach wheel.
2. Turn the probe counter-clockwise by one-quarter or one-half
turn. Tighten the lock-nut. One complete turn moves the
probe by roughly 0.050" axially.
3. Connect a voltmeter across the white and black wire and give
+5 VDC across red and black. When the probe touches the
tooth, the voltage reading will be 0. When loosened by one-
quarter turn, the reading will be approximately 4.9 VDC. If the
probe is turned three-quarters of a turn, the voltmeter reading
will again drop to 0. Move the probe such that it is somewhere
in between one-quarter and three-quarters of a turn and the
reading remains at 4.9 VDC. Tighten the lock nut.
The air gap should range between 0.005" and 0.025". In the
factory, the air gap is maintained at approximately 0.015".
A dead band occurs for air gap distance within 0.026”-0.035”
when the signal is lost. The signal reappears within an air gap of
0.036-0.055”. In excess of 0.056”, the signal is lost completely.
NOTE: It is recommended that the air gap be maintained
close to .015".
Cooling System
NOTE: Piping connections, pipe, and weld areas should
be cleaned before assembly or connections with cooling
system. Weld areas must also be cleaned to remove weld
spatter or slag after welding is complete.
Install the cooling pump, heat exchanger, interconnecting piping
and basket strainer as indicated on the supplied drawings and
as explained in the mechanical system installation manual. If the
Cooling Pressure Transducer PT-3 and the Cooling Pressure
Indicator PI-3 are shipped separately from the CST, install the
assembly of PT-3 and PI-3 as shown on the drawings. Verify
that all hose, tting, piping and anged connections are tight to
prevent hydraulic uid leaks.
Fasten the electrical connections to the heat exchanger fan
motor. Secure the electrical connections to the cooling pump
motor. Fasten the electrical connections between PT-3 and the
controller. The wiring in the conduit is mounted on the CST with
Mini-Din connectors for PT-3 already installed on the wiring.
Place the strainer in a position where the drain plug can be easily
removed. Provide over 12 inches of space above the strainer to
allow for basket removal. The Lid-Ease strainer has cast arrow
marks on the body to indicate the direction that the uid must
ow.
In case of a 4” ange style strainer, external support of the
strainer may be required to reduce pipe strain in the system.
This can be accomplished either by supporting the anges or by
providing a base for the bottom of the strainer. Ensure that the top
of the strainer is not more than 3 feet o the ground to allow for
lid removal and maintenance. In the event that the strainer is not
at the highest point in system, the use of valves is recommended
TAC Wheel Cover
Tooth-Wheel
Lock-Nut
Speed Sensor
DZH460 (ST-1)
0V DC
Black Wire
Signal
White Wire
+5V OR + 24 DC
Red Wire
Figure 9 - O/P Shaft Speed Sensor with Cover
