8.5
TVBA Vibration Input
The Vibration Input (IS410TVBAS2B) terminal board acts as a signal interface board for the Mark VIeS YVIB I/O packs.
The TVBA provides a direct vibration interface to Eddy-current (position & velocity), seismic (velocity), Velomitors
(velocity) and accelerometers with integrated outputs (velocity) sensors. The TVBA also provides a dynamic pressure
interface to charge amplifiers.
The terminal board input signals entering through the two 24-point screw terminals are protected against high voltages due to
electrical disturbances via transient suppression. Powering the different sensors and detecting open circuits is accomplished
by jumpers JPxA located to the left of the 37-pin I/O pack connectors and JPxC located to the right of the 24-point screw
terminals.
The input signals are passed on to the I/O packs through 37-pin connectors located on the right side of the TVBA. The TVBA
can be used for either simplex or TMR applications. TMR applications fan the signal to three I/O packs.
Buffered outputs of the input signals are provided to 9 and 25 pin DIN connectors to feed the Bently Nevada
*
3xxx
monitoring system. A bayonet nut connection (BNC) connection for each buffered output is also included to feed third party
monitoring equipment. To configure the output buffers for the proper sensor, use the JPxB jumpers that are located to the left
of the 37-pin I/O pack connectors. The I/O pack inputs channels 1 through 13 and channels 1 through 14 are routed to
buffered outputs for external use. These BNC and DIN connectors, and the jumper are only available on TVBAH2A,
TVBAH2B, TVBAS2A, and TVBAS2B.
Power is obtained from customer su28 V through the I/O pack.
8.5.1
TVBA Compatibility and Attributes
The I/O pack works with the TVBA terminal board to provide all sensor input checks. The following terminal board revisions
work with the I/O pack.
Terminal Board
Compatibility
Buffered Output
Circuits, DIN, and
BNC Connectors
WNPS
Connectors
IEC61508
Safety Certified
Allows Mixing of I/O
Pack Revisions
†
TVBAS2B
‡
YVIBS1A and YVIBS1B
Yes
No
Yes
No
†
Mixing I/O pack revisions on a TMR module does not allow for Enhanced mode of operation.
‡
N28 power is generated internally to TVBAS2B.
8.5.2
TVBA Installation, Operation, and Jumper Configuration
The TVBA accepts 14 sensor inputs that are wired directly to two 24-point I/O terminal blocks. Each block is held down with
two screws accepting up to #12 AWG wires. A shield termination attachment point is located adjacent to each terminal block.
The I/O pack can only process 13 of the 14 channels. The 14th channel is forwarded to the buffered output stage for use by
the Bently Nevada equipmen.
8.5.2.1
Accelerometers with Integrated Outputs
The TVBA supports accelerometers with integrated outputs on channels 1, 2 and 3 only when the Tracking filters are
required. If broadband rms vibration is all that is required, then all eight channels are available to use. For example, Oil & Gas
LM1600, LM2500 or LM6000 gas turbine applications use the Bently Nevada 86517 sensor. The 86517 is powered by -24 V
and the velocity output is connected to the vibration inputs: PRxxH and PRxxL. Tie the shield on the Mark VIeS end and
leave the shield open on the sensor side preventing ground loops.
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GEH-6855_Vol_II
GEH-6855_Vol_II Mark VIeS Functional Safety Systems Volume II
Public Information