Download DMSSCT Shelf-Mount Solid-State Code Transmitter

Vital Relays and Timers
Ansaldo STS USA
(Formerly known as Union Switch & Signal)
RSE-4C3
Rev. 7-05
DMSSCT Shelf-Mount Solid-State Code Transmitter
For decades, electromechanical code transmitters
have been used to generate the pulses of coded
track circuits. While these transmitters are
reliable performers, their precise, somewhat
complex mechanisms require periodic inspection
and maintenance. ASTS USA has developed a
more cost-effective, yet equally reliable
alternative. The DMSSCT is a solid-state option
for the ASTS USA shelf type DM mechanical code
transmitter. This relay also provides a costeffective alternative to previous shelf-mount solidstate code transmitters.
General Description
The new shelf-mounted DMSSCT solid state code
transmitter is designed to be a functional electronic
replacement for the ASTS USA DM electromechanical
and previous DM solid-state code transmitters
(“cookie jar” style). This relay generates standard
code rates of 75, 120 and 180 codes per minute
(CPM) and is housed in an ASTS USA W-400
transformer style enclosure with top-mounted AREMA
(AAR) wiring terminals. Internal electronics are
divided between two printed circuit boards (PCBs) - a
Timing PCB and an Output PCB. The Timing PCB
generates timing signals used to actuate the switching
circuits at the designated rate, while the Output PCB
contains the switching circuitry.
The DMSSCT contains four pairs of output switches.
Each switch pair has three connections - front (F),
back (B), and heel (H). The number associated with
each connection denotes the switch pair. For
example, “1F” is the front connection and “1B” is the
back connection of the switch pair “1.” Functionally,
the relay is designed to switch the heel (H) connection
between the front (F) and back (B) connections at a
specific rate. Four back switches are actuated
simultaneously by the front output controller. Four
back switches are actuated simultaneously by the
back output controller.
Since the DMSSCT is a solid state replacement for an
electromechanical unit, its circuits are designed to
emulate the toggling, or pendulum action, of relays.
With a code transmitter relay, an electromagnet
attracts and then releases an armature - the resulting
motion alternately closes and opens an opposing pair
of contacts. As with a pendulum, there is a neutral
To order, call 1-800-652-7276
e-mail: [email protected]
position where neither set of contacts is closed,
consequently, the “on” time for each (front and back)
circuit is less than 50% of one full on-off cycle.
Dielectric strength of the unit is 2000 Vac rms
between all external isolated connections and case,
except across open switches which are limited by
Transzorb or metal oxide varistors (MOV) protection.
Maximum voltage is determined by a Transzorb to
protect the DC switches from excessive voltage
spikes when operating code-following relays. For the
AC version, a 150 Vac rms MOV is similarly used
anticipating 120 Vac rms as the source voltage.
Advantages
•
•
•
•
•
•
Direct option for previous ASTS USA DM series
shelf relays.
Provides all required code rates.
No periodic inspection required.
Easy reconnection from “cookie jar” unit top wiring
to W-400 style wiring
No rewiring of external circuits required.
Protected against reversed voltage.
www.ansaldo-sts.com
RSE-4C3, p. 1
Ansaldo STS USA
DMSSCT Shelf-Mount Solid-State
Code Transmitter
(Formerly known as Union Switch & Signal)
RSE-4C3
Rev. 7-05
Outputs:
4 pairs of front-heel-back
(Form C)
Temperature:
-40°C to +70°C (-40°F to
+158°F)
Low Voltage: AC/DC 2.5A,
32 Vdc maximum or 22 Vac
rms maximum, “on”
resistance = 0.5 Ohms (short
circuit protected).
Humidity:
Non-condensing at 0 to 95%
humidity
High Voltage: AC only, 4.0 A,
150 Vac rms maximum, AC
only. External 6A fuse
required for short circuit
protection. Voltage drop
across switch = 1.25 Vac
rms, independent of current.
Ordering and Additional Technical Information
Specifications
Power Input Voltage:
8 to 16 Vdc (reverse voltage
protected operating range)
Current Consumption: 100mA maximum
Output Switch Rating:
•
•
Refer to ordering tabulation for DMSSCT part
numbers.
Request ASTS USA Service Manual SM-8524-A
for additional information.
DMSSCT Code Transmitters
Order No.
N40701601
Code
Rate (CPM)
72
Contact
Config.
4F/4B
Contact
Voltages
L.V.
N40701602
72
4F/4B
H.V.
N40701603
72
N40701604
123
2F/2B
2F/2B
4F/4B
L.V.: #1, #2
H.V.: #3, #4
L.V.
N40701605
123
4F/4B
H.V.
N40701606
123
N40701607
184
2F/2B
2F/2B
4F/4B
L.V.: #1, #2
H.V.: #3, #4
L.V.
N40701608
184
4F/4B
H.V.
N40701609
184
2F/2B
2F/2B
L.V.: #1, #2
H.V.: #3, #4
RSE-4C3, p. 2
DM ElectroMech. Relay
Replaced
N242040
N242041
N242046
N276412
N242042
N242043
N242045
DM SolidState Relay
Replaced
N32001507
N32001504
--
N221553
N221558
N221554
N221556
N221560
N32001506
N221552
N221559
N221555
N221557
N221561
N32001505
N32001503
--
N32001502
N32001501