6
Hold-off Time Delay
- The single-turn adjustment controls the
amount of time that motion must be sensed before the SFD-2 will
change from its “no-motion/no-flow” condition to its “motion/flow”
condition. Clockwise rotation of the potentiometer will increase
the time required for such activity from .25 to 15 seconds. The
delay permits the user to adjust the sensor to ignore unwanted
sensing caused by equipment vibration or short durations of
material flow.
Hold-on Time Delay
- The single-turn adjustment controls the
amount of time that no-motion must be seen before the SFD-2
will change from its “motion/flow” condition to its “no-motion/ no-
flow” condition. Clockwise rotation of the potentiometer will
increase the time required for such activity from .25 to 15 sec-
onds. The delay permits the user to adjust the sensor to ignore
momentary material stoppages induced by shifting or settling of
material.
Fail-safe
(See Figure 13) Selection of the fail-safe mode will per-
mit the output contacts to be signaled in a manner which assures
proper control of loads in the event of SFD-2 sensor/power fail-
ure. Depending on which condition is most critical to signal (flow
or no-flow), the selection can be made by positioning the slide
switch to the desired state.
FLOW - When no-motion/no-flow is sensed, the relay will be
energized. The relay will de-energize when motion/flow occurs,
or if sensor/power failure occurs.
NO-FLOW - When motion/flow is sensed, the relay will be
energized. The relay will de-energize when no-motion/no-flow
occurs, or if sensor/power failure occurs.
All SFD-2 units are set to the NO-FLOW fail-safe configuration
prior to shipping. The terminal block designations represent the
condition of the relay contacts as if all power was off.
POWER SUPPLY/CONDITIONER INDICATORS
1) Green LED
- Illumination of the Green LED indicates power
is properly connected to the power supply/conditioner PCB.
Failure to illuminate indicates that the input AC voltage is improp-
erly connected, the fuse is blown, or that the power supply/con-
ditioner is damaged.
2) Yellow LED
(and external indicator) - The Yellow LED indi-
cates whether the motion detected by the sensor is above the
threshold established by the sensitivity adjustment. Illumination
of the Yellow LED indicates the threshold has been reached. Its
state is not affected by the time delay settings.
PROBLEM: The SFD-2 does not provide relay activation
upon material flow.
CAUSE/SOLUTION:
1) Verify electrical power is connected to proper
terminations and that the sensor is properly
interconnected to the power supply conditioner.
2) Verify sensitivity settings and increase if necessary.
3) Verify hold-off delay setting and decrease if necessary.
4) Verify material flow at sensor face. Eliminate any
conductive buildup. Reevaluate sensor position and
move if increased disturbance can be detected
elsewhere.
PROBLEM: The SFD-2 provides relay activation without
material flow.
CAUSE/SOLUTION:
1) Verify interconnection between sensor and power
supply/conditioner.
2) Verify sensitivity settings and decrease if necessary.
3) Verify hold-on delay and decrease if necessary.
4) Verify movement at sensor face. Reevaluate sensor
position if motion from augers, conveyors or other
material movement causes sensing.
WARNING: The SFD-2 is a maintenance free product and shall
be serviced by Monitor Technologies LLC only. No cleaning is
required. Changes or modifications to the SFD-2 not expressly
approved by Monitor Technologies LLC could void the user’s
authority to operate the product.
NOTE: This equipment has been tested and found to comply
with the limits for a Class B digital device, pursuant to Part 15 of
the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference in a residential and
industrial installations. This equipment generates, uses and can
radiate radio frequency energy and, if not installed and used in
accordance with the instructions, may cause harmful interfer-
ence in radio communications.
However, there is no guarantee that interference will not occur in
a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be deter-
mined by turning the equipment off and on, the user is encour-
aged to try to correct the interference by one or more of the fol-
lowing measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between SFD-2 and receiver.
- Connect the SFD-2 to a different circuit different
from which the receiver is connected.
- Consult the dealer or a radio/TV technician for help.
Figure 13
TROUBLESHOOTING
MAINTENANCE
3) Red LED
(and external indicator) - The Red LED indicates the
condition of the output relay. Illumination of the red LED indi-
cates the output status of the relay is in the “motion/flow” condi-
tion. Its state is influenced by the time delay settings.