GE Hydran 201i, Инструкция по эксплуатации

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Chapter 9 • Communications and Networking
9-2 Rev. 6, March 2011 Part 17997
– One shielded pair to transmit serial communications.
–
For the Hydran 201Ci -1 only : One shielded pair for the TDM (time division multi-
plexing) signal transmitted by the H201T i (see Section 9.1.1 on page 9-2).
• Each supervisory link is electrically isolated and protected (2,000-V RMS opto-couplers,
gas arresters, capacitors and tranzorbs) to withstand at both ends (H201T i and H201C i )
surges up to 2,000 V RMS as well as the large noise transients and ground potential
differences typically found in electrical substations.
• Bidirectional data communication is transparently passed by the H201C i between the
supervisory link port, the RS-485 LAN connector and the RS-232 Computer Port or USB
connector. The communication path is half-duplex (one direction at a time, from a single
talker).
The supervisory link cable can be connected at the following locations:
• In the H201T i : To the Supervisory Link and Analog Output Termination Board (item 9
in Figure 2-4 on page 2-8).
• In the H201C i -C: To the terminals 21 to 24 of the Main Terminal Block (item 5 in
Figure 3-2 on page 3-3).
• In the H201C i -1: To the terminals 21 to 24 of the Main Terminal Block (item 6 in
Figure 3-6 on page 3-11).
9.1.1 TDM Pulse
The TDM pulse is used only with the Hydran 201C i -1 Controller to transfer two pieces of
information from the Hydran 201T i to the H201C i -1 itself:
• Actual dissolved gas level : This analog signal varies from 0 to 100 % (0 to 2,000 ppm)
with a resolution of 1 part in 4,000.
• Alarm relays status : This digital information has four possible values, namely Normal,
High, High-High and Fail.
The relationship between the alarm relay states, and the status of the H201T i , of the TDM
signal and of the H201C i -1 is shown in Table 9-1 on page 9-3.