Bentley 3500/42 Proximitors ®/ Earthquake monitoring module

Wiring specifications

Proximitor sensor: The power supply (PWR) is connected to -24 Vdc, the signal (SIG) is connected to the channel input, and the shielding layer (SHLD) is grounded.

Seismic sensors (such as Velomitor) require series connection of resistors and capacitors (such as 4 k Ω resistors+10 μ F capacitors) for signal conditioning.

TMR wiring: In discrete configuration, three sensors are connected to independent channels of three modules, and in bus configuration, sensor signals are shared through a Bussed Terminal Block.

Maintenance and testing

Regular verification testing

Testing cycle: It is recommended to conduct it once a year. If the equipment is a critical unit or operates in harsh environments, it can be shortened to once every quarter.

Testing equipment: function generator, multimeter, oscilloscope, Keyphasor Multiplier/Diverder, etc.

Test steps (taking radial vibration channel as an example):

Simulate sensor signals (such as a 100 Hz sine wave with a peak to peak value of 2 V).

Verify the display accuracy of proportional values such as Direct and 1X Amplitude (error ≤ ± 1% of full scale).

Trigger Alert/Arm 1 and Danger/Arm 2 thresholds, confirm that the alarm delay time is consistent with the configuration.

Disconnect the input signal and verify the OK state recovery time (Timed OK Channel Defeat set to 30 seconds).

Scale factor and zero position adjustment

Scale Factor: Used to calibrate the linearity deviation of sensors, such as the default 200 mV/mil for 3300-8 mm Proximitors, which can be adjusted by ± 15%.

Zero Position: For channels such as thrust position and eccentricity, adjust the voltage to make the displayed value zero (such as setting the zero position of thrust position to -9.75 Vdc, corresponding to mechanical zero position).

Recorder output verification

The 4-20 mA output should correspond to the full-scale proportional value. For example, when the full-scale is 10 mil pp, 20 mA corresponds to 10 mil pp, and 4 mA corresponds to 0 mil pp, with an error of ≤± 1%.

Troubleshooting

LED fault diagnosis

OK light off: It may be due to module failure, hardware malfunction, or sensor disconnection. Check the power and wiring, restart the module, or replace spare parts.

BYPASS light on: The channel is bypassed by software or the sensor is faulty. Check the Software Switches configuration and confirm that the sensor is in an OK state.

TX/RX light does not flash: communication failure, check the rack backplane connection and serial port parameters (baud rate, data bits).

Analysis of System Event List

Event 11 (Flash Memory Failure): Flash memory failure, module replacement required immediately.

Event 62 (I/O Module Mismatch): The I/O module type does not match the software configuration. Check the module model and reconfigure it.

Event 493 (Kph Lost): Keyphasor signal loss. Check the Keyphasor sensor and wiring to confirm if the speed is within the valid range (60-60000 cpm).

Common alarm handling

Alert/Arm 1 trigger: If the vibration value exceeds the threshold, check whether the machine is unbalanced, misaligned, or has bearing faults.

Trigger of Danger/Arm 2: Emergency stop condition, immediately stop the machine and troubleshoot equipment faults. If the shaft displacement exceeds the limit, it may cause dynamic and static friction.

Technical specifications and ordering information

key parameter

Input impedance: Proximitor channel 10 k Ω, TMR configuration with bus mode 50 k Ω and discrete mode 150 k Ω.

Frequency response: The radial vibration Direct channel supports 1 Hz-4000 Hz, and the acceleration channel supports 3 Hz-30 kHz.

Environmental conditions: Operating temperature -30 ℃~65 ℃ (non barrier module), storage temperature -40 ℃~85 ℃, humidity ≤ 95% non condensing.

Order Parts

Monitor module: 3500/42-01-00 (discrete internal terminal, no authentication), 3500/42-03-01 (TMR external terminal, CSA authentication).

Spare parts: I/O module (such as 128229-01), terminal block (125808-02 Euro style), cable (129525-0010-01, 10 foot assembly cable).

Safety and Compliance

Explosion proof certification: With barrier module supporting Class I, Division 1 (Groups A-D) and EEx ia IIC, suitable for explosive gas environments.

Static protection: When operating the module, wear an anti-static wrist strap and store it in a conductive bag to prevent static electricity from damaging the circuit board.

Maintenance warning: When hot plugging modules, ensure that the rack is powered off to avoid the risk of short circuit or electric shock caused by live operation.