Acromag Model 4683-TTM-x AC-Powered RS-485 Network ...

INSTRUCTIONS: Model 4683-TTM-x
AC-Powered RS-485 Network Repeaters



These instructions are presented in abbreviated form. Please COMMUNICATION SPECIFICATIONS
visit our web site at www.acromag.com to register and obtain
the complete User Manual 8500-237 for this product. Baud Rates: DIP switch settings on unit for 300, 600, 1200,
2400, 4800, 9600, 19.2K, & 38.4K baud rates. Only one
MODEL DESCRIPTION switch must be closed according to baud rate required for
proper operation.
Model Power
RS-485 Bus Loading: One unit load equivalent.
4683-TTM-1 115V AC
4683-TTM-2 230V AC RS-485 Bus Drive: Complete RS-485 compliance for up to 32
unit loads (31 unit loads if a repeater is used).
These devices are “rugged” RS-485 network repeaters used for
isolating network signals and extending communication End-of-Line Termination Network: Refer to Figure 1. The
distances. Model 4683-TTM-x units are similar to the Acromag EOL termination network is individually selected for both
Model 4SCR-TTM-x models, but add field-selectable, End-Of- the A and B sides by a pair of shorting clips. The A side
Line (EOL) network terminations on board for both the A and B (input) is controlled by jumpers J1 & J2. The B side
sides, and are UL approved. (output) is controlled by jumpers J3 & J4.

Operation is transparent to all other network devices and no The EOL network termination is enabled for the A side or
handshaking is required. Up to 32 RS-485 devices can be the B side when the associated pair of jumpers are
driven. These repeaters are enclosed in a rugged aluminum positioned over pins 1 and 2. The EOL termination is
enclosure and come ready to mount on any base plate, or can disabled (removed from circuit) when the pair of jumpers
be installed into a NEMA enclosure for harsh environments. are positioned over pins 2 and 3.

Installation is as simple as mounting, setting the baud rate, Duplex: Half duplex only.
connecting and terminating the network, and connecting power.
Data Format: Ten bits typical (1 start bit, 8 data bits, and 1
FEATURES stop bit). Other formats are supported.

● No handshaking & No extra control lines required. Status Indicators: Red power LED; red RS-485 bus fault
LED’s, side A and side B; green transmit LED’s, A-to-B
● Full I/O signal isolation. and B-to-A.

● Supports baud rates of 300, 600, 1200, 2400, 4800, 9600, PHYSICAL SPECIFICATIONS
19.2K, and 38.4K, switch-selectable.
Operating Temperature: 0 to 70° C (32 to 158° F).
● Field-selectable, End-of-Line (EOL) network terminators on
both the A (input) and B (output) sides. Relative Humidity (RH): 10 to 95% RH (noncondensing), up
to 40° C (104° F).
● Transient protection installed to help protect connected
devices from destructive noise spikes and line transients. Power: 115VAC ±10%, 50/60 Hz, 0.05A (Model 4683-TTM-1);
230VAC ±10%, 50/60 Hz, 0.03A (Model 4683-TTM-2).
● Status LED’s indicate transmission direction, RS-485 bus
fault conditions, and power. Power Line Fuse: 0.5A, 250V, 3AG type. Refer to Figure 1
for fuse location.
● 115VAC and 230VAC models supported.
Isolation: Unit includes galvanic and optical isolation between
OPERATION RS-485 side A, RS-485 side B, AC power, and chassis
ground. Common mode voltages of up to 250Vrms, or
The Model 4683-TTM-1 & 4683-TTM-2 network repeaters are 354V DC (withstands a 1500V AC dielectric strength test
used to isolate and boost RS485 signals and extend network for 1 minute without breakdown), are permitted on a
distance. Each repeater will permit the addition of up to continuous basis. This complies with test requirements
another 32 devices to a network, and extend the outlined in ANSI C39.5-1974 for voltage ratings specified.
communication distance another 4000 feet.
RFI Resistance: Withstands an RFI field strength of 10V per
The repeater has two “sides” referred to as side A and side B. meter at 27MHz, 151MHz, and 467MHz with no digital
Side A typically connects to the network towards the host (input effect, per SAMA PMC 33.1 test procedures.
side). Side B connects to the extended network (output side).
Functionally, sides A and B are equivalent. Transient signal Line Noise Effects: Field and power line terminals withstand
protection is provided on both RS-485 sides. When both RS- ANSI/IEEE C37.90-1978 Surge Withstanding Capability
485 lines are idle, each side is in the receive mode. When a (SWC) Test with no component failures. Unit is tested to
one to zero transition is detected (signifying a start bit) on either a standardized test waveform that is representative of
side, the opposite side’s transmitter is enabled (half-duplex). surges (high-freq. transient electrical interference),
The transmitter stays enabled for one character’s time (based observed in actual installations.
on the baud rate switch setting). The character received is then
passed through. Communication Connections: Network repeater – both RS-
485 connections use modular terminal blocks with screw
The repeater receives AC power through a three-screw terminal clamps. Wire range is 14 to 26 AWG CSA approved.
strip. Input power is fused and isolated. Model 4683-TTM-1
units require 115VAC, 4683-TTM-2 units require 230VAC. Power Wire Connections: Network repeater terminal block.
See label on unit for power to be applied to unit.

Approvals: UL Listed, CSA Certified file LR25710.

Shipping Weight: 3.0 pounds (1.4 kg) packed per unit.


Acromag Incorporated, 30765 South Wixom Road • P.O. Box 437 • Wixom, MI • 48393-7037, USA
Phone: (248) 624-1541 • Fax: (248) 624-9234 • E-mail: [email protected] • On-Line: http://www.acromag.com

Copyright 1990, Acromag, Inc. Printed in the USA. 8500-267-B04C016

REPEATER INSTALLATION Setting The Baud Rate

Mounting The unit includes an 8-position DIP switch (S1) along the
bottom edge. This switch is used to set the baud rate of the
Refer to Figure 1 below for mounting and clearance repeater. Only the switch that corresponds to the required
dimensions. baud rate should be closed (refer to label information next to
S1)—all other switches must be left in the OPEN position.
This device is packaged in a rugged aluminum enclosure and
no auxiliary enclosure is required for most applications. Electrical Connections (Refer To Drawing 4501-783)
Mounting holes are provided for surface mounting the unit. You
may use an auxiliary enclosure to protect the unit in Terminals can accommodate wire from 14-26 AWG, solid or
unfavorable environments or vulnerable locations. stranded.

Termination Jumpers 1. Network - Input (Side A) & Output (Side B): Connect unit
as shown in Figures 3 and 4. Be sure to enable EOL
Any RS-485 network will require that the network be properly termination as required at the ends of the network. Make
terminated at the ends of a network, or network segment. sure the baud rate DIP switches are set to match the data
Termination is usually found at the first and last node of a rate of the network.
network segment. Since a repeater is used to segment a
network, two sets of termination resistors will be required. One 2. Power: Connect AC power as shown in Figure 4 according
at the input side, one at the output side. to model number. Input power is fused (3AG type, 0.5A,
250V). Refer to Figure 2 to locate this fuse if the red power
Model 4683-TTM-X units include selectable End-Of-Line (EOL) LED fails to light with power applied.
termination resistors that can be enabled or disabled by
positioning jumper blocks on headers installed on the circuit 3. Ground: Ground unit at AC input ground (G) terminal. The
board (see Figure 2). You will have to remove the top cover to chassis is common to this earth ground connection.
gain access to these jumpers. Be sure to turn power OFF
before removing the cover or setting these jumpers. Simply
remove the single screw on each side of the enclosure and
slide the top cover off. Refer to Figure 2 of the following page
to locate and set these jumpers as required for your installation.
Optionally, you may leave these jumpers in their disabled
position and attach 120Ω termination resistors externally,
between the RT terminals adjacent to the network connections.

RS-485
SIDE A

RT
RT
D
D
COM
NC
RS-485
SIDE B
RT
RT
D
D
COM
24VDC
RTN
24VDC

4.30 3.70 acromag
(109.22) (93.98)

FAULT 1 - 300 5 - 4800 BAUD 12345678 TX TX FAULT
A RATE S1 B-A
2 - 600 6 - 9600
POWER 3 - 600 7 - 19.2K A-B B
4 - 2400 8 - 38.4K

0.30 6.40 0.30
(7.62) (162.56) (7.62)
TYP
TYP 7.0
(177.80) FIGURE 1

2.10 MODEL 4683-TTM-X REPEATER
(53.34) MODEL 4SCR-TTM-X REPEATER
MECHANICAL DIMENSIONS

Acromag, Inc. Phone: (248) 624-1541 • Fax: (248) 624-9234 -2- • E-mail: [email protected] • On-Line: http://www.acromag.com

EOL JUMPERS EOL Jumpers
EQUIVALENT CIRCUIT Side A (IN)
(4683 UNITS ONLY)
1 1 Status Baud Rate Status
2 2 LED's Switches LED's
3 3

J1 J2 J1 J2

EOL EOL

Vcc DISABLED ENABLED FAULT TX TX S1 FAULT
1200 OHMS B-A 87654321 A
B A-B 1 - 300 5 - 4800 POWER
BAUD 2 - 600 6 - 9600
JUMPER PAIR RATE 3 - 600 7 - 19.2K
(ONE SIDE)
4 - 2400 8 - 38.4K

321 D REMOVE THIS SCREW ON EACH F1

220 OHMS SIDE TO REMOVE COVER

321 D EOL Jumpers FUSE 3AG
0.5A, 250V
Side B (OUT)
1200 OHMS

1 1 1 1
2 2 2 2
3 3 3 3

J4 J3 J4 J3 J4 J3 J1 J2

EOL EOL

DISABLED ENABLED

FIGURE 2 24VDC
RTN
MODEL 4683-TTM-1 REPEATER
MODEL 4683-TTM-2 REPEATER 24VDC
End-of-Line (EOL) Termination Jumper Locations. COM
Input Power Fuse Location.
D
D
TR
TR

RS-485
SIDE B
NC
COM
D
D
TR
TR
RS-485
SIDE A

RS-485 RS-485 G W L1 4683-TTM-1 (115VAC)
SIDE B SIDE A G L2 L1 4683-TTM-2 (230VAC)

COM D D COM D D AC (HI)
AC (LO)
GROUND

NETWORK CONNECTIONS

HOST PC FIGURE 3 NETWORK SEGMENT 2
RS-232
MODEL 4683-TTM-X REPEATER (EXTENDED NETWORK)
STATION CONFIGURATION UP TO 4000 FEET

NETWORK SEGMENT 1
UP TO 4000 FEET

RS-485 RS-485 INPUT OUTPUT RS-485 RS-485
(SIDE A) (SIDE B)
120 OHM TERMINATION
RESISTOR REQUIRED A-N2 A-N3 A-N4 A-N5 B-N2 B-N3 B-N4 B-N5 B-N32

THIS END Acromag
RUN
120 A-N1 A-N32 B-N1
ST
AC INPUT Acromag Acromag Acromag Acromag Acromag Acromag Acromag Acromag
TB 1 RUN RUN RUN RUN RUN RUN RUN RUN DFT
01
RS-232C ST ST ST ST ST ST ST ST
COM
Rx DFT DFT DFT DFT DFT DFT DFT DFT
Tx 01 01 01 01 01 01 01 01

TB 2
RS-485

RT
RT
D
D
COM
24VDC
RTN
24VDC
RS-485
SIDE A
RT
RT
D
D
COM
NC
RS-485
SIDE B
RT
RT
D
D
COM
24VDC
RTN
24VDC

acromag MODEL 4SCC-TTM-1 UP TO 32 acromag MODEL 4683-TTM-1 UP TO 32
MODEL 4SCC-TTM-2 MODEL 4683-TTM-2
RR RR NODES PER RR RR NODES PER R
NETWORK NETWORK
SEGMENT SEGMENT

1 - 300 5 - 4800 123 456 78 1 - 300 5 - 4800 123 456 78

2 - 600 6 - 9600 BAUD 2 - 600 6 - 9600 BAUD
3 - 600 7 - 19.2K RATE 3 - 600 7 - 19.2K RATE
4 - 2400 8 - 38.4K 4 - 2400 8 - 38.4K
POWER 232 > RS485 485 > POWER FAULT TX TX FAULT
A
S1 485 FAULT 232 S1 B-A A-B B

RS232-TO-RS485 SIGNAL CONVERTER SIGNAL REPEATER ANY RS-485 DEVICE 120 OHM TERMINATION
RESISTOR REQUIRED
ANY RS-485 DEVICE SIDE-A EOL TERMINATION SIDE-B EOL TERMINATION AT END OF NETWORK
NO TERMINATION RESISTOR JUMPERS ENABLED JUMPERS ENABLED
OR LAST DEVICE ONLY

OPTIONALLY, YOU MAY CONNECT TERMINATION RESISTORS EXTERNALLY

BETWEEN THE RT TERMINALS ADJACENT TO THE NETWORK CONNECTIONS
FOR SIDE A AND SIDE B, BUT THE INTERNAL JUMPERS MUST BE SET TO
DISABLED WHEN USING EXTERNAL TERMINATION.

The station configuration drawing of Figure 3 is for general illustration purposes only. Johnson
Controls customers should instead refer to the Metasys® Network Technical Manual for N2 Bus
Communication connections using the 4683-TTM-x repeater.

Acromag, Inc. Phone: (248) 624-1541 • Fax: (248) 624-9234 -3- • E-mail: [email protected] • On-Line: http://www.acromag.com

TRANSMIT DIRECTION HOST PC
RS232-TO-RS485 AND RS485-TO-RS232
RED RS485 FAULT LED

SET BAUD RATE AT S1

RED POWER LED

485 > RS485 232 > S1 1 - 300 5 - 4800 POWER -1 OPTION -2 OPTION RS232 CONNECTIONS
232 FAULT 485 8765 4321 2 - 600 6 - 9600 115VAC 230VAC TO HOST COMPUTER

BAUD 3 - 600 7 - 19.2K L1 AC (HI) L1 AC (HI)
RATE 4 - 2400 8 - 38.4K W AC (LO) L2 AC (LO)
G Ground G Ground
S1 - SET BAUD RATE RS232 TO RS485 CONVERTER SIGNALS AT HOST
TO MATCH BAUD CONVERTER DB25
RATE OF NETWORK.
MODEL 4SCC-TTM-X acromag RX 2 TX
S1 - BAUD RATE 3 RX
1 - 300 5 - 4800 TO HOST B
2 - 600 6 - 9600 TX
3 - 1200 7 - 19.2K
4 - 2400 8 - 38.4K A

GROUND RTS
CTS
24VDC 1 2 3 4 5 6 7 8 9 10 11 12 13 DB25 COM 7 DSR
RTN 14 15 16 17 18 19 20 21 22 23 24 25 COM
C CD
24VDC
COM

D
D
TR
TR

TB 2
RS-485
Tx
Rx
COM

TB 1
RS-232C
AC INPUT

NC

A-N1 ABC POWER L1 W 115VAC OR HOST
A-N2 DE9
120 OHM
TERMINATION CONNECTION L1 L2 230VAC 2 TX
REQUIRED
12 345 DE9 RX 3 RX
6789
B
TX

A

RS232 COM 5 COM

RR C

ANY A-N3 NOTE: JUMPERED PINS ARE
RS485 NULL-MODEM CONNECTIONS
DEVICES UP TO 32 WHICH ALLOW COMMUNICATION
NODES PER BETWEEN THE HOST AND
NETWORK ACROMAG SERIES 4100/4200
SEGMENT I/O STATIONS.

RR A-N30 FIGURE 4

A-N31 MODEL 4SCC-TTM-X CONVERTER
MODEL 4683-TTM-X REPEATER
SYSTEM CONNECTIONS

-1 OPTION -2 OPTION RS485 RS485 EXTENDED NETWORK
115VAC 230VAC A-N32
B-N2 B-N3 B-N4 B-N5 B-N32
L1 AC (HI) L1 AC (HI)
W AC (LO) L2 AC (LO)
G Ground G Ground

SEE UNIT LABEL B-N1
TO VERIFY POWER
NC
REQUIREMENTS
RS-485
IMPORTANT: SIDE A
MODEL 4683-TTM-X UNITS
INCLUDE INTERNAL, FIELD RT
SELECTABLE END-OF-LINE RT
(EOL) TERMINATION D
RESISTORS FOR THE A AND D
B SIDES. THESE ARE COM
ENABLED VIA INTERNAL NC
JUMPERS. DO NOT USE RS-485
EXTERNAL TERMINATION SIDE B
WITH INTERNAL EOL RT
JUMPERS ENABLED. RT
D
D
COM
24VDC
RTN
24VDC

UP TO 32

NODES PER

RS485 REPEATER NETWORK
MODEL 4683-TTM-X
acromag R R R R SEGMENT R

NOTE: SIDE-A AND SIDE-B EOL
TERMINATION JUMPERS ENABLED

FAULT 1 - 300 5 - 4800 BAUD 1234 5678 TX TX FAULT
A 2 - 600 6 - 9600 RATE S1 B-A A-B B

POWER 3 - 600 7 - 19.2K 120 OHM TERMINATION
4 - 2400 8 - 38.4K
RESISTOR REQUIRED
ANY RS-485 DEVICE AT END OF NETWORK

RED POWER LED S1 - SET BAUD RATE RED RS485 FAULT LED (SIDE B) OR LAST DEVICE ONLY
RED RS485 FAULT LED (SIDE B) TO MATCH BAUD
RATE OF NETWORK. TRANSMIT DIRECTION
RS232-TO-RS485 AND RS485-TO-RS232
S1 - BAUD RATE
1 - 300 5 - 4800
2 - 600 6 - 9600
3 - 1200 7 - 19.2K
4 - 2400 8 - 38.4K

The system connection drawing of Figure 4 is for general illustration purposes only. Johnson Controls
customers should instead refer to the Metasys® Network Technical Manual for N2 Bus Communication
connections using the 4683-TTM-x repeater.

Acromag, Inc. Phone: (248) 624-1541 • Fax: (248) 624-9234 -4- • E-mail: [email protected] • On-Line: http://www.acromag.com