Hints – Westermo MD-62 User Manual

Page 6

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12

6070-2001

Hints

If any problems occur upon set-up of the MD-62, the following notes may be helpful.

1. Power up the MD-62 and check that

the PWR LED is lit.

2. Check the cable between your RS-232

interface and the RS-232 connection on
the MD-62. The RS-232 interface on
the MD-62 is configured as DCE (Data
Communication Equipment). Most prin-
ters, PCs and terminals are set as DTE
(Data Terminal Equipment).
See 3 suggestions of cable configura-
tions on the next side.

How to check whether the equipment is
DTE or DCE:

Power up the unknown equipment and
ensure that nothing is plugged into the
RS-232 interface. Using a multi-meter,
first measure the voltage on pin 2 of the
connector (male or female) with refe-
rence to ground on pin 7 (25 pole
connector) or on pin 5 (9 pole connec-
tor, PC standard). Then measure the
voltage on pin 3 in the same way. The
pin with the most negative voltage will
be the output pin and will identify the
device as DCE or DTE.

25 pole connector RS-232-C

If the most negative voltage is on pin 2:
the device is DTE.

If the most negative voltage is on pin 3:
the device is DCE.

9 pole connector,PC standard

If the most negative voltage is on pin 3:
the device is DTE.

If the most negative voltage is on pin 2:
the device is DCE.

3. The RS-232 cable is correct but it still

does not work. The LEDs may be helpful.

PWR: The unit has power

RD:

Data received from fibre interface

TD:

Data received from RS-232 interface

RTS: RTS from RS-232 side

CTS: Indicates RTS from RS-232 side

on oppsite modem.

4. Test each individual modem. All switches

in OFF state. Make sure that the mains-
power socket is disconnected when the
modem lid is off.

A. Equipment required: a terminal or a PC

with terminal program, an RS-232 cable
according to point 2, and a fibre cable.

B. Connect a cable between the modem

and terminal, or PC with a terminal
program. Connect the fibre cable bet-
ween RX and TX.

C. Press any key on the keyboard. During

keystrokes, the TD and RD LED’s
should flash on the modem, simultane-
ously, the characters will be echoed on
the monitor.

D. If the fibre cable is removed from one

port only, the TD LED will flash when
a key is pressed, but no characters will
appear on the screen.
Repeat the same test with the second
modem.

5. Testing the modems together.
A. Leave the last tested modem in place,

connected to the terminal or the PC
(modem A).

B. Connect two fibre cables between the

modems RX (modem A) – TX
(modem B) and vice versa.

C. Connect pins 2 and 3 of the RS-232

interface on modem B
(top screw terminal 7, 8).

D. Continue according to point 4.C.

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