Pulsafeeder Pulsar DLC User Manual

Page 71

7.2.19.1 Loopback Test Procedure

The Loopback test is helpful in the identification of wiring errors. While this menu is displayed the
DLC transmits and expects to receive characters back. The display shows the percent (%) of successful
characters exchanged.

The Loopback test requires the installation of a Loopback device at the end of the cable segment under
test. This can be constructed according to Figure 17 below:

Figure 17 – Loopback Device Wiring Diagram

– – Loopback Test Procedure – –

a) Install the line terminator in one port of the

DLC. (J7 or J8)

b) Install the cable under test in the second port.

(J7 or J8)

c) Install the loop back device at the far end of the

cable under test.

d) With the {LOOPBACK TEST YES} screen displayed, press [ENTER].

LOOPBACK TEST

YES

e) While the LOOPBACK test is being conducted, the following screen is displayed:

PLEASE WAIT

TEST IN PROGRESS

When the test is completed, a result screen is displayed:

100.0% SUCCESS
RETRY YES

- or -

100.0% SUCCESS
RETRY NO

f) If the indicated percent of success is 0%, the cable segment is bad. If the indicated percent of

success is 100%, the segment is good. If the success rate is less than 100%, but greater than zero
you may want to lower the baud rate on the network.

6. To exit the diagnostic menu press [UP] and then press [ENTER]. The {–MENU– / SERIAL COMM}

screen is displayed.