Technical Specifications

2.1 Electrical Parameters

Supply Voltage: -17.5VDC ~ -26VDC (standard - 24VDC).

Operating Current: Approximately 12mA (static).

Signal Output:

Gap Voltage (DC): -2V ~ -18V (typical - 10V, corresponding to 1mm gap).

Vibration Voltage (AC): Peak-to-peak 0 ~ 20V (sensitivity 8V/mm).

Frequency Response: 0 ~ 10kHz (vibration signal).

Linear Range: 0.5mm ~ 2.5mm (8mm probe); 0.3mm ~ 1.5mm (5mm probe).

Impedance: Input Impedance > 1MΩ; Output Impedance < 100Ω.

2.2 Mechanical and Environmental Parameters

Shell Material: Metal (aluminum alloy), sealed dustproof.

Installation Method: DIN rail installation (compatible with 7200 system cabinet).

Dimensions: Approximately 114mm × 42mm × 30mm (length × width × height).

Weight: Approximately 0.3kg.

Operating Temperature: -40℃ ~ +70℃.

Storage Temperature: -50℃ ~ +85℃.

Relative Humidity: 5% ~ 95% (no condensation).

Protection Grade: IP65 (dustproof, splash-proof water).

2.3 Model Suffix Definition (72645-XX-02-01-02-03-01-01-14)

72645: Basic model (preamplifier).

XX: Probe compatibility specification (02 = 8mm probe, 01 = 5mm probe).

02: Cable length compatibility (02 = 5m, 01 = 3m).

01: Output signal type (01 = standard vibration + gap voltage).

02: Power supply method (02 = -24VDC).

03: Shell material (03 = aluminum alloy).

01: Connector type (01 = standard BNC).

01: Version Number (01 = initial version).

14: Production Batch / Serial Number.

III. Installation and Wiring

3.1 Pre-installation Preparation

Check the appearance of the preamplifier: no damage, no deformation, connectors intact.

Verify the model: confirm compatibility with the probe and system (72650 series probe + 7200 system).

Environmental Requirements: Install away from strong electromagnetic interference (such as frequency converters, motors), with good ventilation, temperature -40℃ ~ +70℃.

3.2 Installation Steps

Insert the preamplifier into the DIN rail (standard rail in the cabinet), ensure firm fixation.

Probe Side: Insert the extension connector of the 72650 probe into the probe input port of the preamplifier (BNC), tighten the lock nut.

System Side: Connect the preamplifier's signal output port (BNC) to the input port of the 72646B monitoring card using coaxial cable.

Power Side: Connect the positive and negative poles of -24VDC power supply to the power terminals of the preamplifier (+/-), ensure correct polarity (reverse connection protected, will not damage).

Grounding: Connect the grounding terminal of the preamplifier (GND) to the system ground (ground resistance < 4Ω).

3.3 Wiring Terminal Definition Table

Terminal Identification  Function Description

PWR+  Positive terminal of power supply (-24VDC negative terminal)

PWR-  Negative terminal of power supply (-24VDC positive terminal)

GND  System ground

PROBE  Input signal for probe (BNC)

OUT  Output for vibration and gap voltage (BNC)

IV. Debugging and Calibration

4.1 Pre-Startup Inspection

Correct wiring: The power supply, probe, output, and ground connections are correct.

Insulation test: Use a multimeter to measure the insulation resistance between the power supply terminals and the casing > 1MΩ.

4.2 Startup Debugging

Connect -24VDC power supply, and the power indicator light of the preamplifier turns on (green).

Gap voltage measurement: Use a multimeter's DC档 to measure the voltage between OUT and GND. Normally， it should be -8V to -12V (corresponding to a probe gap of about 1mm).

Vibration signal test： Gently shake the probe， and the OUT terminal should have an AC voltage fluctuation (peak-to-peak value changes with the shaking amplitude).

4.3 System Calibration (TK-3E Calibrator)

Install the probe on the calibrator， set the standard gap (such as 1.0mm).

Adjust the calibrator to simulate the standard vibration (such as 100μm peak-to-peak value).

Check the preamplifier output： Gap voltage -10V (±0.5V)， vibration voltage 0.8V peak-to-peak (±5%).

After calibration， fix the probe installation position and lock the nut.

V. Maintenance and Care

5.1 Daily Maintenance (Every Shift)

Visual inspection： The casing has no oil stains， no corrosion， and the connectors are not loose.

Signal inspection： The gap voltage is stable， with no abnormal fluctuations.

Environmental inspection： Temperature and humidity are normal， and there is no strong electromagnetic interference.

5.2 Regular Maintenance (Weekly/Monthly)

Weekly： Clean the casing dust， check the cable fixation， and there is no wear or compression.

Monthly： Use a multimeter to measure the power supply voltage (-24VDC ±1V)， gap voltage (-10V ±1V).

Every six months： System calibration (TK-3E)， check the probe coil resistance (deviation from the factory value < 5%).

5.3 Precautions

Do not plug or unplug the probe or cable while powered on， to avoid damaging the preamplifier.

Do not mix use of probes from different series (such as 72650 and 3300 series)， as it will cause measurement errors.

Avoid water or oil ingress into the preamplifier. In humid environments， take protective measures.

Long-term inactivity： Disconnect the power supply， store in a dry and ventilated environment， temperature -50℃ to +85℃.

VI. Fault Troubleshooting

6.1 No output signal

Possible causes： Power not connected， polarity reversed， fuse blown， probe/connector damaged， connector loose.

Troubleshooting steps：

Check power： -24VDC is normal， and the indicator light is on.

Check wiring： The power supply， probe， and output connections are correct， and there is no looseness.

Probe test： Replace the known intact probe， and if there is output， the original probe is damaged.

Cable test： Use a multimeter to test the continuity of the cable， without open circuit or short circuit.

6.2 Abnormal gap voltage (exceeds -2V to -18V)

Possible causes： Probe gap is too large/ small， probe contamination， extended cable too long， preamplifier failure.

Troubleshooting steps：

Check probe gap： Adjust to about 1mm， clean the probe surface of oil stains and dust.

Check cable length： Match with a 5m extended cable， without additional length.

Calibration test： Use TK-3E calibration， if calibration fails， the preamplifier is damaged.

6.3 Large vibration signal fluctuation

Possible causes： Electromagnetic interference， probe fixation loose， cable shielding damaged， poor grounding.

Troubleshooting steps：

Move away from the interference source： Move to a position far from the frequency converter and motor.

Fix the probe： Lock the installation nut， without looseness.

Check shielding： The cable shielding layer is intact， and grounding is reliable. VII. Spare Parts and Replacement

7.1 Compatible Replacement Models

Original Replacement: 72645 series of the same model (e.g. 72645-02-01-02-03-01-01-14).

Upgrade Replacement: 330180 series of preamplifiers (compatible with 3300 system, requires replacement of probe as well).

7.2 Supplementary Spare Parts

Probe: 72650-30 (8mm), 72650-31 (5mm).

Extension Cable: 726902-5M (5m), 726902-3M (3m).

Connector: BNC connector, anti-loosening nut.

VIII. Safety Instructions

Installation, commissioning, and maintenance must be carried out by professional technicians. Familiarize yourself with this manual and the operation specifications of the 7200 system.

Strictly follow electrical safety regulations. Perform operations with power off to avoid electric shock.

Do not擅自modify or repair the preamplifier without authorization. For faults， contact the original manufacturer or authorized service provider.

Disposal： Follow the industrial electronic waste disposal specifications to avoid environmental pollution.