Led Displays And Troubleshooting; Led Displays - Siemens OLM/P11 V4.0 Operating Instructions Manual

Installation and Maintenance

5.7 LED Displays and Troubleshooting

Notes:
For a valid measurement, that the partner OLM at the other end of the fiber-optic
cable must send normal PROFIBUS frames. This can be recognized by the LED
display of the partner OLM (see section 5.7.1).
The output voltages at the measurement sockets are influenced by many factors:
The measurement sockets are therefore not intended as a substitute for a
calibrated level measuring device with a calibrated light source. The value obtained
only serves to classify the received optical signals in 3 classes:
The measurement must be performed with a standard ungrounded and high-
resistance voltmeter. The internal resistance of the measurement sockets is
approx. 30 kΩ. A connection from the measurement sockets or of reference
potential to the OLM housing is not permitted.
When an OLM of the SINEC L2FO range is connected, the OLM V4 LED level
indicator has no meaning. The measurement sockets cannot be used.
5.7 LED Displays and Troubleshooting
5.7.1

LED displays

Figure 5-13 LED displays on the front panel
Note:
The LED between "SYSTEM" and "CH 1" is unused and does not light up.
SIMATIC NET PROFIBUS, Optical Link Module
Operating Instructions, 07/2008, A2B00065774O, Edition V1.5
strength of the optical transmit power of the partner OLM
ambient temperature of the optical transmitter and receiver
attenuation of the transmission line
transmission rate used
good (normal operation, green)
critical (optical link margin reduced, yellow)
bad (functionality not guaranteed, red)
5V > U > 240 mV
120 mV ≤ U ≤ 240 mV
U < 120 mV
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