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TC2200R/S Bus
User's Manual
Rev. 2.2
5. What is the built-in signal generator and how is it used ?
Ans:
By sliding
SW2_3
("SIG GEN" on the front panel) to the Down position, a pulse signal will be
generated to simulate an incoming signal on the DB25's connector pins 2 & 4 (for an RS-232
interface). In effect, this pulse signal is a simulated broadcast signal from the SCADA host,
which will travel through the fiber to each Slave in the bus. This function is very useful for
troubleshooting and verifying network integrity. The slow pulse rate of the LEDs can be easily
confirmed at any Slave location.
6. What is the difference between the front panel's "Rx-A" and "SynA" LEDs ?
Ans:
"Rx-A" indicates the receiving optical signal strength. When the "RxA" optic signal is above the
sensitivity threshold (typically from -33dBm to -36dBm) the "Rx-A" LED will light (solid). A
marginal or fault condition causes it to flash. In some cases, the "RxA" optic signal is above the
sensitivity threshold but is of poor quality. This will result in an invalid data packet being
received, causing the "SynA" LED to flash.
The possible fault conditions could be one of the following:
A.
Received optic signal's power is marginal (at the borderline of the sensitivity threshold).
B.
Receiver is being overdriven (optic signal strength is too strong).
C.
Multimode cable is used on a Single Mode unit and causes the receiver to be overdriven.
D.
Optic cable is cross-connected with another vendor's product and the TC2200/2201 can not
recognize the data packet being transmitted.
The "SynA" LED lights (solid) when the data packet being received at optic "RxA" is validated.
An invalid data packet will cause the "SynA" LED to flash.
The same applies to the "Rx-B" and "SynB" LEDs for the B-Link.
