This is with reference to the Gas Turbine with TMR mark V system.

The MarkV system was powered off. When it was powered on, the display on R, S, T is not there.
However the display of C core is normal.

The TMR is communicating appropiately with I station. Logic forcing and other things are fine.

The machine is under shutdown. We're clueless, could some help us out?

 

Do you mean the LCD displays on the LCC/SLCC cards are indicating nothing?

They should be indicating the processor status (A4, A5, A6, A7, A8, A9, etc.), the Voter ID (<R>, <S>, or <T>) and the time. If they are not are you certain the power switches in the <PD> core for <R>, <S>, and <T> are on? Are the greed LEDs on the TCPD card in the <PD> core above the fuses for <R>, <S>, and <T> lit?

What is the status indication on <C>'s LCC/SLCC display?

Are the LED bargraphs on the DCC/SDCC cards of <R>, <S>, and <T> flashing any sequences?

How was the power to the Mark V shut down? How was it powered-up?

Are you powering the Mark V from the battery, or directly from the battery charger? (Powering a Mark V from the battery charger without the battery connected to the charger/Mark V is *highly* discouraged, and usually results in lots of problems, not the least of which are blown fuses.

Each of the processors has it's own TCPS card in Loc. 5 of the core (the very back of the core). Each of the TCPS cards gets 125 VDC from the <PD> core. Most of the <PD>s have switches on the TCPD card for each of the processors; very early TCPDs did not have switches and one had to unplug the cable connector to remove the power. While not impossible, it's not likely that all the TCPS cards in <R>, <S>, and <T> have failed.

In the plastic pouches on the backs of the core doors you should find some papers showing the layouts of the cards in the cores. The TCPS card layout shows the locations of the fuses on the TCPSs. If the fuses in the <PD> core are good (and if I recall correctly, the green LEDs above the fuses for the processors will be lit when the fuses are good and the switches are in the ON position) and the switches are in the ON position, then you'd better start looking at the fuses on the TCPSs.

This ain't easy, and the best way to do it is to put the switch in the <PD> core in the off position to remove the 125 VDC to the TCPS being examined, then remove the TCPS in order to be able to see all the fuses and replace any that might have failed. Be sure to note every cable/connector being disconnected in order to be sure they are reconnected, and reconnected properly. The "trace" of the ribbon cable should be oriented to Pin 1 of the connector, which should be silk-screened on the card and shown clearly on the card layout drawings. Ribbon cables in the Mark V are *not* keyed, so they can be installed backwards (as has been reported on control.com recently).

 

Are you really sure that R,S & T are powered up ? You will get comms with only <C>