KM6620 Bearing Vibration Monitoring Instrument

review Machine condition, machine damage, and ongoing damage can be identified in the form of fault symptoms during machine operation. The information transmitted by mechanical vibration is one of them, and almost all mechanical failures will produce excessive vibration. Among all types of vibration, absolute bearing vibration is the easiest to measure, referring to the rapid vibration of the casing (bearing shell and bearing seat) relative to a fixed reference point in space. Speed sensors or piezoelectric sensors can be used to measure in the horizontal and vertical directions of the casing. Installing these sensors is simple and quick, requiring only one screw. Therefore, monitoring absolute bearing vibration is a fundamental and widely used protective measure for most rotating machinery.

The right figure shows the recommended measurement positions for measuring horizontal, vertical, and axial absolute bearing vibration on the main bearing of a steam turbine.

KM6620The bearing vibration monitoring instrument is a dual channel vibration monitoring instrument, with two channels working independently, displaying independently, and inputting signals from two vibration speed sensors. Users can perform different combinations of measurements on two channels, which can be horizontal and vertical points at the same position, or two points at different positions. They can also form independent relays into "AND" and "OR" logic through the rear terminal. For many small and medium-sized rotating machinery, especially those with ball bearings (where shaft vibrations are more easily transmitted to the casing), this is an ideal monitoring and protection instrument that meets the requirements ofAPI670Standard requirements.

Main functions

Two channels（AChannel andBThe independent monitoring and display of channels ensure the reliable and stable operation of each channel. Therefore, the functions described below areATheBAll channels are available.

● range0-50gIn0-50mm/sor0-800umInternally optional, customized by the user during instrument selection, pre-set by the manufacturer.

● Display function:

The vibration amplitude value (displacement value), velocity and acceleration, alarm value, and function code of the bearing are respectively located inLEDDisplayed on the display window.

The indicator lights of different colors on the panel are used to indicate the working status of the instrument panel.

● Alarm function:

Users can set their own "alert" and "danger" values for vibration. When the vibration of the unit reaches or exceeds the "alert" or "danger" value set by the instrument, the corresponding indicator lights on the panel will indicate the "alert" and "danger" alarm states, and the rear panel terminals will provide relay outputs.

● Alarm delay function:

This function of the instrument increases the reliability of the alarm. Users can choose the delay time for triggering the warning and danger relays when selecting the instrument. This function is pre-set by the manufacturer or set by the user themselves.

● Alarm reset function:

When an alarm occurs, the alarm reset is divided into two methods: self-locking and automatic reset; When self-locking, the alarm function is always maintained. After the monitoring situation is normal, the "reset" button needs to be pressed to reset; When resetting automatically, the alarm function will be automatically released after the monitoring situation is normal. Users can choose one of the methods when selecting instruments, which is pre-set by the manufacturer or set by the user themselves.

● Self diagnostic function:

The processor performs self checks on the instrument measurement circuit at regular intervals and monitors the working condition of each channel measurement circuit. If any input system malfunction, such as probe rupture, poor contact, circuit failure, etc., is detected and an error code message is displayed on the display window, then“OK”The light flashes, and both the "alert" and "danger" alarm circuits are disconnected.

● Sensor power supply current limiting protection:

When a sensor power short circuit occurs accidentally during use, the current limit should be ≤10mAIt will not cause a fire and meets the safety requirements of the monitoring site.

● Record output:

Output analog signals proportional to the bearing vibration range on the terminal block of the rear panel, while providing4-20mASignal. The output terminals are designed with short-circuit protection function.

● Sensor signal buffer amplification output: The buffered and amplified sensor signal is output from the rear panel terminal block.

● Panel setting function:

The parameters and function settings of the instrument can be set in real-time through the buttons on the panel, with smooth and convenient switching.

1． Technical Specification

● Frequency response:0.5～10KHzInternal grading is optional, and the bandpass filter is pre-set by the manufacturer based on the equipment condition.

● Sensor selection: Our company is selected for low-speed equipmentICPPiezoelectric accelerometerKM7750DSelection of medium speed equipmentKM7760It can also be matched with sensors from other manufacturers.

● Input:

sensor input ICPPiezoelectric accelerometer

Input Range (0.5~5)V/G

Instrument constant current source 4.3mA（24Vdc）

Input points 2point

● System input/Output conversion accuracy (including sensors):

Record output ±1%(Full range) 25℃

digital display ±1%(Full range) 25℃

● Record output (rear panel terminal):

4-20mA(Maximum load)500(h)

Raw signal buffer output (rear panel terminal): The sensor's raw signal is buffered and amplified before being output from the rear panel terminal.

● report Police:

Alarm Setpoint 4point A通道(danger1point,alert1point),B通道(danger1point,alert1point)

Relay status Frequent power loss

Alarm relay output4Group normally open relay（Adanger,Aalert,Bdanger,BAlert)

Contact output capacity 250VAC/３Aor30VDC/３A

alarm delay 0～10Can be set in seconds, priority should be given to using 1second

Alarm reset auto-reset,self-locking(optional)Priority should be given to automatic reset.

● ring Environment:

Operating Temperature 0 ∽ 65℃

Storage temperature -30 ∽85℃

relative humidity 20 ∽95%No condensation

● Working power supply:165-265VAC，47-440Hz

● Power consumption:<10tile

● Weight: ＜1.5KG

1． Display and buttonsInstructions

● display window:

The front panel of the instrument panel is equipped with a left（AChannel) Right（BTwo display windows, each with a channel3bitLEDThe digital display tube displays two channel monitoring values during normal monitoring of the instrument; When performing functional operations, display functional parameters.

● status indicator light:

Below the display window on the front panel of the instrument panel, there is a8A light-emitting diode used to indicateLEDThe nature of displayed information, instrument functions, and alarm status are as follows:

AOKandBOK Green, when it is constantly on, it indicates that the system channel is working normally. If it is not on,It indicates that the sensor and the connected circuit are not working properly,Simultaneously cut off the alarm circuit. Need to check sensors and circuits or channels,After troubleshooting,The instrument enters normal monitoring state,The light automatically turns on normally.

AAlert andAdanger AThe warning light is yellow,AThe hazard light is red, used to indicateAAlarm status of the channel,When the amplitude value reaches the alarm value,This light is always on,Alarm relay action. This light works in conjunction with the alarm reset function of the instrument panel,After normal monitoring, press the reset button in the self-locking state,The light just went out. In self recovery state,This light will automatically turn off when the alarm is cleared.

BAlert andBdanger BThe warning light is yellow,BThe hazard light is red, used to indicateBAlarm status of the channel,When the amplitude value reaches the alarm value,This light is always on,Alarm relay action. This light works in conjunction with the alarm reset function of the instrument panel,After normal monitoring, press the reset button in the self-locking state,The light just went out. In self recovery state,This light will automatically turn off when the alarm is cleared.

ABypass andBbypass yellow,Side lights are used to indicate whether the relay is in an alarm state. If the bypass light is not on, it means that if the alarm value is set, when the display reaches the alarm value, the relay will act and the bypass light will be on. If the alarm value is set, when the display reaches the alarm value, the relay will not act.

● Button Instructions

On the instrumentFunctional OperationsWhen switching between different settings, store the set parameter values in the machine, and then enter the next parameter setting state;

On the instrumentFunctional OperationsWhen, shift the digital loop to the left1Position;

On the instrumentFunctional OperationsWhen, increase the corresponding digit1；

Clear the instrument's memory of alarm status and danger, reset the relay,During the parameter setting process, pressing this key will exit the current parameter setting.

2． Parameter Setting Instructions

In the parameter setting state, the left display window on the panel displays the parameter category to be set, and the right display window displays the parameter status (parameter value) to be set.

press The key can cyclically change the number of digits required to set parameter values, while the corresponding digit's digital display flashes.

press The key can increase the current flashing value1Thus, the numerical values can be adjusted from0to9Cycle changes.

Note: At any time during the above setup process, pressThe reset button can terminate the current setting

Rear panel terminal wiring diagram:

Terminal block connection:

Attention：1Please do not use blank terminals.

2. The piezoelectric acceleration sensor to the instrument terminal uses a two core shielded cable, and the shielding layer adopts a single ended grounding method: the shielded wire is floating with the sensor end and with the instrument endSHLDConnect.

3. Insulation resistance between instrument ground and casing ground500VDC≥500MΩ, allowing the chassis to be directly connected to the control panel

Connect the screen to the ground.

Connection of signal transmission cables

1When connecting piezoelectric acceleration sensors to instruments or acceleration sensors to safety barriers, as well as safety barriers to instruments, please ensure the use of two core shielded cables as the transmitted signals may be interfered with.

2Avoid signal transmission cables and control cables220VACThe power cables are wired together.

3Install all cables in conduits or place them on cable racks.

4The recommended requirements for using cables are as follows: mesh shielded cable (core wire is soft copper wire).

5. System verification and maintenance:Vibration calibration table

６．Unpacking and Installation

After opening the instrument packaging,Each instrument has one installation bracket, one certificate of conformity, and one user manual.

The installation position and structure of the instruments on the control cabinet are shown in the following figure:

Terminal block connection:

Attention：1Please do not use blank terminals.

2. The piezoelectric acceleration sensor to the instrument terminal uses a two core shielded cable, and the shielding layer adopts a single ended grounding method: the shielded wire is floating with the sensor end and with the instrument endSHLDConnect.

3. Insulation resistance between instrument ground and casing ground500VDC≥500MΩ, allowing the chassis to be directly connected to the control panel

Connect the screen to the ground.

Connection of signal transmission cables

1When connecting piezoelectric acceleration sensors to instruments or acceleration sensors to safety barriers, as well as safety barriers to instruments, please ensure the use of two core shielded cables as the transmitted signals may be interfered with.

2Avoid signal transmission cables and control cables220VACThe power cables are wired together.

3Install all cables in conduits or place them on cable racks.

4The recommended requirements for using cables are as follows: mesh shielded cable (core wire is soft copper wire).

5. System verification and maintenance:Vibration calibration table

６．Unpacking and Installation

After opening the instrument packaging,Each instrument has one installation bracket, one certificate of conformity, and one user manual.

The installation position and structure of the instruments on the control cabinet are shown in the following figure:

Insert the fixing rods into the installation slots on the left and right sides respectively, and then tighten them with installation screws.

Attention:If users have special requirements for instrument functions, additional design and development are required. The model number will be marked with the word "non-standard" and a dedicated user manual will be provided with the instrument