Control Components



216D and 217D Track Diodes

Waterproof and highly surge resistant, the 216/217 Series Diodes also offer extra-low insertion loss, notably high current capacity and are repairable. Our Diode was the only brand diode that the surge generator of a major railroad could not blow up. Field tests indicate that our Diode can offer a gain in circuit length, shunting improvement and "hold-in" capacity in bad track conditions. Because the high-current diode itself is heat-sinked, current capacity of our Track Diode exceeds practical limits of the transformer end of the circuit. Aging and burnout of the diode has, for all practical purposes, been eliminated. Further, a unique sealing process allows resealable access to all the components should repair become necessary. Track wires are each 4 feet long.

ORDERING REFERENCES
Description Part Number
Diode In Clear Case less/Mtg Clamps 216D
Diode In Clear Case w/Mtg Clamps 216DK
Diode In Opaque Case w/Mtg Clamps 217D


Track Circuit Components 215A Track Power Unit and AC Source Unit

AC/DC, Style "C" track circuits have long been recognized for their ability to work properly in rusty rail and bad track environments, and for their ease of maintenance. Adding to our unique Model 216/217 Track Diode, S & C Distribution Company is offering a complete, building-block type, AC/DC track circuit system, including the AC Signal Source and Track Power Units that feed the Track Diode(s). Expanding on the attractive features of AC/DC type circuits in general, use of the AC Source/Track Power Unit concept, which operates on 8-15 VDC, provides a track circuit system that will continue to operate after commercial power has failed, as long as the standby battery has the capacity to power it.

The building-block Model 215A AC/DC Track Circuit System consists of the AC Signal Source Unit (PN: 215B-2), Track Power Unit (PN: 215A-1), and Track Diode (PN: 217D - see above). These building-blocks can be combined to create a wide variety of track circuit configurations. The 215A System offers the advantage of operating on DC power while creating a square wave AC signal to feed the track diode.

Our use of a square-wave AC signal creates optimum shunting characteristics. Because of the very high voltage spikes that are generated by the square-wave signal, shunting characteristics of such signals are superior to DC and even AC sine-wave type signals.

Up to six Track Power Units (TPU's) can be fed by one AC Source Unit (ACSU), allowing a common phase and frequency to be maintained throughout the track circuit group. Using this capability, short approach warning is guarded against by alternating phase alignment on the rail in each circuit.

Single 215A Track Circuits are ideally suited to OS and Fouling Circuit applications. See following information on the 215 AC/DC Single Track Circuit Panel. Additional information is available in sales and application literature.



ORDERING REFERENCES
Description Part Number
215A Track Power Unit 215A-1
215A AC Source Unit 215B-2


40 Volt Auxiliary Surge Network

The 40 Volt Auxiliary Surge Network protects our Track and Slide Fence/High Water Detector Power and AC Source Units from surges that get through primary track, line and power-side arrestors. It should not be used as a standalone device.

By holding all five inputs and outputs to a common value not to exceed 200V, it prevents damage caused by fast moving initial spikes and metallic surges resulting from unbalanced circuits. The protective theory employed has been well-proven in the service performance of our Track Diode. Circuits operating through the device should not exceed 38VDC, 38VAC, peak to peak.

The Surge Network mounts directly to either our 215A-1 Track Power Unit or our 215A-10 Slide Fence and High Water Detector Power Unit in lieu of field wiring. Field wiring then connects to the Network. Additional information is available in sales and application literature.

ORDERING REFERENCES 215A-18


215 AC/DC Single Track Circuit Panel

S&C Distribution Company is pleased to make available a prewired panel, suitable for backboard or 19" rack mounting, that includes all track circuit specific components for one circuit, except the safety relay. Can be ordered with or without the 40 Volt Auxiliary Surge Network. This handy package makes the job of circuit conversion or new circuit installation a very easy process. When ordering, specify track and limit resistor values.

ORDERING REFERENCES
Description Part Number
Circuit Panel w/o Aux Surge Network 215-1020
Circuit Panel w/Aux Surge Network 215-1021


Model 200 Slide Fence Pull-Aparts

A modern solution to an old problem. For use with hog-wire type slide fences. Rugged, UV inhibited plastic housing and lid, with interlocking weather seal. Pull-apart pins are conductive stainless steel. Double pin union requires 40 foot pounds pull to disengage. Comes complete with fence-attaching eye and water-tight couplings for wiring. Slack-adjusting turnbuckle available as an accessory.

ORDERING REFERENCES
Description Part Number
Double-Pin Pull-Apart 200-2
Turnbuckle, Slack Adjust 200-2-3


205 Series High Water Detectors

S & C Distribution Company provides a unique series of circuiting solutions to another old problem. Three different High Water Detector options offer two DC versions, one requiring 8 wires from the control case and one requiring four wires; and one AC/DC version requiring two wires. In addition to the simplicity of a two wire circuit, the AC/DC version offers improved sensitivity to less conductive water, without responding to normal nighttime condensation, and the ability to connect Detectors in series to allow one power source to activate a network of Detectors covering as much as 54 linear miles.

The major advances in High Water Detector design actually start with the Detector itself. Maintenance considerations, such as ease of access (lid lifts off, bringing with it all internal components - see above drawings) and ease of testing (Detector is designed to stand off from its mounting post allowing testing with a five gallon bucket half-filled with water) make the Model 205 High Water Detector a very practical device.

Water enters the tube, and drains from it through screened ports drilled in the bottom. Similar screened ports at the top of the Detector insure against air pressure resisting the rise of the water. Water contacting the electrodes shorts the circuit, causing the HWPR relay to de-energize.

Application literature includes circuiting recommendations that incorporate a push-button reset to guard against wave action causing the high water indication to cycle on and off, and forcing the presence of someone capable of evaluating the condition that resulted in detection. An alternate circuit provides for protection against electrolysis resulting from the Detector(s) remaining under water for an extended period of time.

ORDERING REFERENCES
Description Part Number
High Water Detector, 8 wire, DC 205-1
High Water Detector, 4 wire, DC 205-2
High Water Detector, 2 wire, AC/DC 205-3


215A Slide Fence & High Water Detector Circuits

Our highly successful AC/DC, Style "C" building block track circuit equipment has been modified to address the unique needs of slide fence and high water detector applications. Using this equipment offers several advantages:
  1. High voltage (14 and 28 VAC) output for working through long, possibly high-resistance circuits.
  2. Circuit distances of up to 54 miles are possible
  3. Configurable so that a short anywhere in circuit will cause a detection, rather than a false-clear failure.
  4. Low current drain allows use of Model 215 equipment at remote locations where solar power is the only option
  5. If powered by commercial power, following power failure, the 215A-10 Power Unit and the 215B-2 AC Source Unit will continue to operate as long as the associated standby battery has the capacity to power them.
  6. Diode is housed in a rugged, stand-alone, waterproof housing and has superior, built-in lightning protection.

Full application details are available on both the Slide Fence and High Water Detector Circuits. See also above information on the 40 Volt Auxiliary Surge Network accessory available for use with the 215A-10 Power Unit.


ORDERING REFERENCES
Description Part Number
215A SF & HWD Power Unit 215A-10
215A AC Source Unit 215B-2


215 AC/DC Single Slide Fence and High Water Detector Circuit Panel

We are pleased to make available a prewired panel, suitable for backboard or 19 in. rack mounting, that includes all the circuit specific components for one circuit, except the safety relay. Can be ordered with or without the 40 Volt Auxiliary Surge Network. This handy package makes the job of circuit conversion or new circuit installation a very short process.

ORDERING REFERENCES
Description Part Number
Circuit Panel w/o Aux Surge Network 215-2020
Circuit Panel w/Aux Surge Network 215-2021


POK Strobe Light

S&C Distribution Company is pleased to offer a unique solution to the problem of power off indication. Our 120 POK Strobe Light is turned on when commercial power fails, rather than being turned off. It is much easier to see an active strobe light, particularly when your primary concern is the possible presence of fuel trucks, etc., at the crossing, rather than looking for something that is off. Over the years, widespread use of this light has established a nearly 100% success rate at having power-off conditions reported from the field, usually by train crews. Further, because it is only on when an alarm condition exits, vandalism rates are a small fraction of those recorded for conventional power-off indicators.

While POK service at highway crossing warning locations is a primary application, other locations where our Strobe Light is in service include hot box detector and train control signal sites. The product we offer is unusually well suited to the purpose. Two operating voltages are offered; 6 to 10VDC and 6 to 24VDC. Two activation methods are available; industrial relay and 120-30 Voltage Sensor (see following). Contact us for more application information.

ORDERING REFERENCES
Description Part Number
POK Strobe Light, 6-10VDC 120-10
POK Strobe Light, 6-24VDC 120-24
PO Relay, 120VAC 120-16
PO Relay, 240VAC 120-17


Model 120 DC Voltage Sensor

Easy-to-apply activator for various PO indicators. Specifically designed as activator for the S&C Mode 120 POK Strobe Light, however the unit can drive assorted DC relays (200mA relay drive output) or provide inputs to recorders or other reporting devices. This unit is field-configurable to allow for an output either when sensed voltage is present, or when it is not present. Green LED indicates Input voltage presence and Yellow LED indicates Output presence. Sensor features very low current usage during monitoring operations. Unit is designed to respond to storage battery output thus, checking commercial power, battery charger and the operating battery itself. Any failure in the chain will be detected and alarmed. Monitors DC voltages from 6 to 30 VDC. Range selection is made on installation. Fine tuning of the detection point is accomplished with an adjustment pot. Set this unit to detect when the float charge to the battery drops. Additional application details are available.

ORDERING REFERENCE 120-30DC