Description
Technical Parameters
Product Introduction
The Servo Control (IS200VSVOH1BDC) board controls four electro-hydraulic servo valves that actuate the steam/fuel valves. These four channels are divided between two servo terminal boards (TSVO or DSVO). Valve position is measured with linear variable differential transformers (LVDT). The VSVO provides a position loop control algorithm that runs in firmware and a hardware current regulator that provides the servo output current.
Technical Specifications
|
Manufacture |
General Electric(GE) |
|
Model |
IS200VSVOH1BDC |
| Part Number | IS200VSVOH1B |
|
Description |
VSVO Servo Control
|
|
Origin |
USA |
|
Dimension |
35*25*8cm |
|
Weight |
0.35kg |
Product Details
Three cables connect to each VSVO: the J5 plug on the front panel, and the J3 and J4 connectors on the backplane. Each VSVO can connect to two TSVO terminal boards, and each TSVO can connect to three VSVOs. TSVO provides simplex signals through the JR1 connector, and fans out TMR signals to the JR1, JS1, and JT1 connectors. Plugs JD1 or JD2 are for external trips from the protection module.
Three LEDs at the top of the VSVO front panel show status information. The normal RUN condition is a flashing green, and FAIL is solid red. The third LED is STATUS and is normally off but displays a steady orange if an alarm condition exists on the board.Diagnostic checks include the following:
• The output servo current is out of limits or not responding, which creates a fault.
• The regulator feedback (LVDT) signal is out of limits. A fault is created and if the associated regulator has two sensors, the bad sensor is removed from the feedback calculation and the good sensor is used.
• The servo has suicided. This creates a fault.
• The A/D converter calibration voltage is out of limits and a default value is being used.
• The LVDT excitation voltage is out of range. A fault is created
• The input signal varies from the voted value by more than the TMR differential limit.This causes a fault to be created indicating a problem with this sensor input
• If any one of the above signals go unhealthy a composite diagnostic alarm,L3DIAG_VSVO, occurs. Details of the individual diagnostics are available from the toolbox. The diagnostic signals can be individually latched, and reset with the RESET_DIA signal if they go healthy.
• Connectors JR1, JS1, JT1 on the terminal board have their own ID device that is interrogated by the I/O board. The ID device is a read-only chip coded with the terminal board serial number, board type, revision number, and the plug location.When the chip is read by VSVO and a mismatch is encountered, a hardware incompatibility fault is created.
IS200VSVOH1B Installation：
To install the V-type board
1. Power down the VME processor rack
2. Slide in the board and push the top and bottom levers in with your hands to seat
its edge connectors
3. Tighten the captive screws at the top and bottom of the front panel
IS200VSVOH1B Operation：
The VSVO provides four channels consisting of bi-directional servo current outputs, LVDT position feedback, and LVDT excitation. The VSVO also provides two pulse rate flow sensor inputs. The TSVO provides excitation for, and accepts inputs from, up to six LVDT valve position inputs. There is a choice of one, two three, or four LVDTs for each servo control loop. Three inputs are available for gas turbine flow measuring applications.These signals come through TSVO and go directly to the VSVO board front at J5.
Each servo output is equipped with an individual suicide relay under firmware control that shorts the VSVO output signal to signal common when de-energized, and recovers to nominal limits after a manual reset command is issued. Diagnostics monitor the output status of each servo voltage, current, and suicide relay.
VSVO Simplex Systems
VSVO circuits for a simplex system are shown in the following figures.
Each servo output channel can drive one or two-coil servos in simplex applications, or two or three-coil servos in TMR applications. The two-coil TMR applications are for 200 psi oil gear systems where each of two control modules drive one coil each and the third module interfaces with the servo. Servo cable lengths up to approximately 300 m (1000ft) are supported with a maximum two-way cable resistance of 15 ohms. Because there are many types of servo coils, a variety of bi-directional current sources are selectable
by configuring jumpers.
A trip override relay, K1, is provided on each terminal board and is controlled by a contact closure from the <P> Protection Module. If an emergency overspeed condition is detected in the Protection Module, the K1 relay energizes, disconnects the VSVO servo output from the terminal block, and applies a bias to drive the control valve closed. This is only used on simplex applications to protect against the servo amplifier failing high, and is functional only with respect to the servo coils driven from <R>.
VSVO TMR Systems
In TMR applications, the LVDT signals on TSVO fan out to three racks through JR1, JS1,and JT1. Three connectors also bring power into TSVO where the three voltages are diode high-selected and current limited to supply 24 V dc to the pulse rate active probes. VSVO circuits for a TMR system are shown in the following figures.
