Black Box High Speed SHM-B Async User manual

JANUARY 1995
ME802A
ME802AE
ME802C
High Speed SHM-B Async
High Speed SHM-B Async Card
CUSTOMER SUPPORT INFORMATION
Order toll-free in the U.S. 24 hours, 7 A.M. Monday to midnight Friday: 877-877-BBOX
FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax [phone]
Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
HIGH SPEED SHM-B ASYNC
RD
TD
NORMAL
DLB

HIGH SPEED SHM-B ASYNC AND CARD
FEDERAL COMMUNICATIONS COMMISSION
AND
INDUSTRY CANADA
RADIO FREQUENCY INTERFERENCE STATEMENTS
This equipment generates, uses, and can radiate
radio frequency energy and if not installed and
used properly, that is, in strict accordance with the
manufacturer’s instructions, may cause interference
to radio communication. It has been tested and
found to comply with the limits for a Class A
computing device in accordance with the specifi-
cations in Subpart J of Part 15 of FCC rules, which
are designed to provide reasonable protection
against such interference when the equipment is
operated in a commercial environment. Operation
of this equipment in a residential area is likely to
cause interference, in which case the user at his own
expense will be required to take whatever measures
may be necessary to correct the interference.
Changes or modifications not expressly approved by
the party responsible for compliance could void the
user’s authority to operate the equipment.

HIGH SPEED SHM-B ASYNC AND CARD
This digital apparatus does not exceed the Class A limits
for radio noise emission from digital apparatus set out in
the Radio Interference Regulation of Industry Canada.
Le présent appareil numérique n’émet pas de bruits
radioélectriques dépassant les limites applicables aux
appareils numériques de la classe A prescrites dans le
Règlement sur le brouillage radioélectrique publié par
Industrie Canada.
TRADEMARKS USED IN THIS MANUAL
UL is a registered trademark of Underwriters
Laboratories Incorporated.
Any other trademarks mentioned in this manual are acknowledged to be the property
of the trademark owners.

HIGH SPEED SHM-B ASYNC AND CARD
Contents
Chapter Page
1. Specifications .........................................................1
2. Introduction...........................................................4
3. Installation .............................................................5
3.1 Four-Wire Connections...............................5
3.2 EIA-232 Connection ....................................7
3.3 Jumper Settings ...........................................9
3.4 Flow Control ................................................9
3.5 ME800 Compatibility.................................11
4. Operation.............................................................12
5. Rackmount Installation.......................................15
6. Troubleshooting ..................................................17

1
CHAPTER 1: Specifications
1. Specifications
Transmission —
Data Rate (bps) Max. Distance (miles)
115,200 1.5
56,000 1.7
19,200 2
2,400 4
NOTE: The transmission specifications are for 24-AWG unshielded
twisted-pair cable with a mutual capacitance of no more than
15 pF/ft. Shielded twisted-pair cable will reduce the distance to
one-third of the table value, because of the additional capacitance
contributed by the cable’s shielding. Actual distances may vary,
depending on your specific operating equipment and the cable
you use.
Protocol — Asynchronous
Operation — 4-wire, full duplex, point-to-point
Line Interface — Balanced current loop; Receive
lines are protected through optical isolators rated
at 2500 volts.

2
HIGH SPEED SHM-B ASYNC AND CARD
Equipment Interface — EIA-232/CCITT V.24
interface with hardware-handshake support. Carrier
Detect (CD) true (high) indicates that the short-haul
modem at the remote end of the loop is on and
active. Interface is jumper selectable for DTE/DCE
configuration.
Connectors — (1) DB25 female, (1) 4-screw terminal
block
Diagnostics — Loopbacks provided by a front-panel
switch: Analog loopback on the 4-wire loop and
digital loopback on equipment interface
(EIA-232).
Status Indication — Two light-emitting diodes
(LEDs) indicate the status of the transmitter and
receiver. When the LED is on, it indicates a “high”
logic level is present on the appropriate RS-232 lead.
Enclosure — Mild steel
Compliance — FCC Class A, Subpart J of Part 15;
CSA; UL®
Order Information — ME802A: 115-VAC stand-
alone unit; ME802AE: 230-VAC standalone unit;
ME802C: Rackmount card unit; RM007: 8-card
desktop rack; ME810: 16-card rack for 19" cabinets

3
CHAPTER 1: Specifications
Temperature
Operating — 32 to 140°F (0 to 60°C)
Storage — -4 to 158°F (-20 to 70°C)
Humidity — 0 to 95% max., noncondensing
Power — ME802A, primary: 115 VAC ±10%,
60 Hz;
ME802AE, primary: 230 VAC ±10%,
50/60 Hz; Both, secondary: 17 VAC, 5 watts
Size — ME802A, ME802AE: 1.5"H x 4.4"W x 4.1"D
(3.8 x 11.2 x 10.4 cm);
ME802C: 0.9"H x 3.9"W x 4.5"D (2.3 x 9.9 x 11.4 cm)
Weight — ME802A, ME802AE: 2 lb. (0.9 kg),
including transformer;
ME802C: 0.5 lb. (0.2 kg)

4
HIGH SPEED SHM-B ASYNC AND CARD
The High Speed SHM-B Async is an asynchronous
full-duplex 4-wire line driver/receiver. With a pair of
these devices, two EIA-232 devices can com-municate
at distances of up to 4 miles (6.4 km) and at data
speeds of up to 115.2 Kbps. In addition to the
transmitter and receiver circuits, the High Speed
SHM-B Async includes EIA-232 control-line
interfaces, status monitor LEDs, and a loopback
switch. The High Speed SHM-B Async is available in
both a standalone version (ME802A or ME802AE)
and a rackmount card version (ME802C).
The High Speed SHM-B Async is designed to operate
over a 4-wire metallic circuit. The best performance
is obtained with twisted-pair cable (see Chapter 1).
Most types of twisted-pair cable may be used;
however, to achieve maximum performance, we
recommend Level 4 or Level 5 UTP cable.
The High Speed SHM-B Async is designed for
maximum operator safety. There are no voltages
greater than ±9 VDC or 17 VAC present on the
circuit board of the unit. The Receive lines are
protected from potential ground differences
through optical isolators rated at 2500 volts.
2. Introduction

5
CHAPTER 3: Installation
3. Installation
Installation involves three steps: four-wire
connections, EIA-232 connection, and jumper
settings.
3.1 Four-Wire Connections
Figure 1 shows the location of the terminal block
on the circuit board. Refer to Figure 2 to make the
proper connections between two High Speed
SHM-B Async units.
NOTE: Transmit + (TX+) on one modem is wired to Receive + (RX+) on
the other modem; Transmit - (TX-) is wired to Receive - (RX-).
1.Insert the wires into the terminal strip; tighten the
screw terminals.
2.After you have made all four connections, wrap the
nylon cable tie (included) around the wires. Pull the
tie tight around the wires to secure them to the
printed circuit board. Trim the excess nylon tie with
wire cutters or scissors.

6
HIGH SPEED SHM-B ASYNC AND CARD
Figure 1. High Speed SHM-B Async board:
locations of jumpers and 4-screw terminal block.
J1 RS-232 CONNECTOR
DCE
LOOPBACK SWITCH
RX+
RX- TX+
TX-
DTE
XW1A
XW1B
A B C
W2
A B C
W4
A B C
W3