GE DS3815RVTA

Key Parameters

Relay Output Section:

• Output Channels: 16 or 24 Form-C (SPDT) relay outputs (depending on configuration)

• Relay Type: Standard single-coil or dual-coil latching (field-configurable)

• Contact Rating: 5A at 250V AC / 30V DC (resistive load)

• Output Coil: 24V DC (from backplane or external supply)

• Diagnostics: Per-channel LED status, coil fault detection, contact weld detection (dual-coil variant), fuse status indication, self-test on power-up

• Response Time: 10–15ms (relay operate time)

Vibration Input Section:

• Input Channels: 4 independent vibration input channels

• Input Types: Accelerometer (IEPE/ICP®), velocity (mV/mm/s), proximity probe (eddy-current), or general-purpose voltage (jumper-selectable per channel)

• Signal Conditioning: Integrated IEPE excitation (constant current), charge amplifier, integration (velocity to displacement), and programmable filtering

• Excitation: 24V DC, 4mA constant current (IEPE)

• Frequency Range: 0.5 Hz to 10 kHz (programmable high-pass and low-pass filtering)

• Resolution: 16-bit ADC with ±0.1% accuracy

• Measurement Parameters: Acceleration (g), Velocity (mm/s or in/s), Displacement (µm or mils) – software-selectable integration

• Diagnostics: Per-channel LED status, transducer fault detection (open/bias/overload), over-range detection, signal quality monitoring

Common Section:

• Isolation: 2500V RMS channel-to-backplane

• Field Wiring: Integrated terminal blocks for direct field wiring

• Temp Range: –40°C to +85°C (extended)

• Power Supply: +5V (logic), +24V (relay coils and field power) from backplane or external supply

• Physical: 6U VME single-slot board

• Key Features: Integrated relay outputs + vibration inputs, Form-C contacts, 5A contact rating, IEPE excitation, programmable filtering, extended temp range, high isolation

Advantages

• Integrated relay + vibration – the DS3815RVTA combines high-current relay outputs and vibration monitoring in a single module, reducing board count and simplifying system architecture.

• Space-saving – replaces up to three separate boards (relay output, vibration input, and excitation supply) with one module.

• Relay outputs for trip/alarm actuation – 5A Form-C contacts directly drive solenoids, alarms, and contactors based on vibration thresholds.

• Dual-coil reliability option – redundant coil drive for critical vibration trip circuits (field-configurable).

• Contact weld detection – monitors relay contact status for early warning of failure.

• Vibration signal conditioning – built-in IEPE excitation, charge amplification, filtering, and integration eliminate external signal conditioners.

• Multi-parameter vibration measurement – can output acceleration, velocity, or displacement from a single sensor input.

• Transducer diagnostics – detects open circuits, bias faults, and overload conditions.

• Programmable filtering – the General Electric DS3815RVTA allows setting high-pass and low-pass filters to reject unwanted noise.

• Extended temperature range – operates from –40°C to +85°C for harsh environments.

• Comprehensive protection – over-voltage, over-current, and thermal protection safeguard the board and connected field devices.

• High isolation – 2500V RMS isolation protects the backplane from field-side faults.

• Drop-in compatible – works with all Mark IV backplanes and processor configurations.

Applications

• Turbine vibration trip systems – the DS3815RVTA monitors vibration levels and actuates trip relays when thresholds are exceeded.

• Vibration alarm annunciation – drives panel lamps, horns, and DCS alarm inputs based on vibration alarms.

• Bearing vibration monitoring with relay output – monitors bearing housing vibration and provides relay outputs for alarm or shutdown.

• Shaft vibration monitoring – measures relative shaft vibration using proximity probes and actuates protection relays.

• Condition monitoring with discrete control – provides vibration data for trending while maintaining relay outputs for critical protection.

• Offshore and harsh environments – extended temperature range makes it suitable for demanding applications.

• Retrofits – replaces separate relay and vibration boards with a single, integrated solution.

vs Competitors & Separate Boards

Selection Tips

• Vibration monitoring + relay control – choose the DS3815RVTA when you need both vibration monitoring and relay outputs for alarm/trip actuation in a single module.

• Slot-limited installations – the General Electric DS3815RVTA reduces board count compared to separate relay and vibration boards.

• IEPE accelerometer compatibility – the built-in IEPE excitation eliminates the need for external signal conditioners.

• Critical vibration trip applications – configure the dual-coil relay option for redundant coil drive.

• Sensor compatibility – verify that your vibration sensors (accelerometer, velocity, proximity probe) are supported.

• Filtering requirements – configure the high-pass and low-pass filters to reject noise while preserving the vibration frequency band of interest.

• Harsh environments – the extended temperature range makes it suitable for offshore, desert, or unheated cabinet installations.

• Spare strategy – keep one DS3815RVTA per 5–8 installed units, especially in critical vibration protection applications.

• Wiring planning – plan field wiring terminations carefully to leverage the integrated terminal blocks efficiently.

• Calibration – periodically verify vibration measurement accuracy using a portable vibration calibrator or reference sensor.

Critical Precautions

• IEPE sensor power – for IEPE accelerometers, ensure the DS3815RVTA excitation voltage and current (typically 24V DC, 4mA) are correctly configured. Incorrect settings can damage the sensor.

• Proximity probe compatibility – eddy-current probes require specific excitation voltage and calibration; verify the General Electric DS3815RVTA is configured for the correct probe type.

• Frequency range – set the high-pass and low-pass filters appropriately. Too high a high-pass cutoff can miss low-frequency vibration components; too low a low-pass cutoff can let noise through.

• Integration selection – when selecting velocity or displacement output, ensure the integration algorithm is correctly configured.

• Sensor wiring – use shielded twisted-pair cables for vibration sensor connections. Ground the shield only at the DS3815RVTA end to prevent ground loops.

• Output over-current – do not exceed the relay contact rating (5A). Overloading can weld contacts or cause overheating.

• Inductive loads – for DC solenoid and relay coil loads, install a flyback diode across the load to prevent voltage spikes from damaging the DS3815RVTA relay contacts or control circuitry.

• Contact weld detection – if contact weld detection is triggered, verify the relay contact status and replace the DS3815RVTA if a contact is welded.

• Relay contact wear – for high-cycle applications, consider derating the contacts or using an external interposing relay.

• Field wiring – use appropriate wire gauge for field connections. Loose connections can cause intermittent faults or overheating.

• Fuse replacement – if a fuse status indicator shows a fault, verify the field wiring and load before replacing the fuse. Use only the specified fuse rating.

• Ground loops – use single-point grounding for all vibration sensors and relay outputs connected to the DS3815RVTA.

• Thermal considerations – ensure adequate cabinet cooling (>250 CFM); the DS3815RVTA can generate significant heat under full load.

• Self-test – allow the DS3815RVTA to complete its power-up self-test (~2 seconds) before relying on outputs or measurements.

• Calibration intervals – schedule periodic calibration verification (every 6–12 months) to maintain accuracy.

• Hot-swap – never insert or remove the DS3815RVTA while the rack is powered.

• ESD handling – always use a grounded wrist strap.

• Storage – store spare DS3815RVTA boards in anti-static bags in a dry, temperature-controlled environment.