Vibration is often the result of components that are imbalanced, misaligned, worn, loose, or improperly driven. Detecting increased vibration early can help reduce machine damage, avoid failures, and reduce downtime. Vibration monitoring is an effective form of predictive maintenance. It is also a good way to monitor machine run time.
What types of machines should be monitored?
Any rotating machinery should be monitored for vibration, such as motors, pumps, compressors, fans, blowers, gear boxes, etc.
How does the QM42VT1 measure vibration?
It uses a MEMS based accelerometer as its core sensing element and advanced signal processing techniques to output a digital signal that represents a true RMS velocity between 10 and 1,000 Hz.
Why does the QM42VT1 measure velocity?
Velocity, acceleration, and displacement can all be measured. Velocity is considered a universal measure of machine integrity because it provides the most uniform measurements over a wide range of machine frequencies.
What does RMS velocity mean?
RMS is the Root-Mean-Square of the velocity. It is in essence an averaging operation that conveys the effective energy produced by the vibration of the machine. It is the most common and effective measure of machine vibration severity in rotating equipment.
What frequency range can the QM42VT1 measure RMS velocity?
The QM42VT1 measures RMS velocity between 10 Hz and 1,000 Hz (1 KHz).
Does the QM42VT1 use an FFT?
Yes, it uses an FFT to convert the vibration signal from a time domain to a frequency domain in order to calculate the velocity.
Is there any vibration analysis that is needed with the data provided by the QM42VT1?
No, the QM42VT1 measures vibration by calculating RMS velocity.
Where should the QM42VT1 be mounted?
Mounting it as close as possible to the bearings will provide the most accurate measurements; however, it can be mounted anywhere on the machine. Regardless of where it is mounted, you can take measurements, establish a vibration baseline, and set thresholds according to the baseline.
How should the QM42VT1 be mounted?
It can be mounted using the two sided thermal transfer mounting tape, standard bracket and a screw, or the magnet bracket (sold separately).
How strong is the hold strength for the magnetic bracket?
25 lbs. of pull force.
When should the screw mount bracket be used?
The screw mount should be used when a very stiff and secure mount is needed.
In how many axes does the QM42VT1 measure vibration?
It measures one axis, the z-axis:
How often does the QM42VT1 take a vibration measurement?
The default sample rate is 5 minutes. For the first 15 minutes after power up however, the node goes into fast sample mode, sampling every second. To exit fast sample mode prior to 15 minutes, click the button 5 times (button 1 on the P6 and H6). Fast sample mode will expire after 15 minutes, to put the node back into fast sample mode single click the button again. The sample rate can also be changed using the UCT.
How do I determine where to set vibration thresholds?
The ISO 10816 Vibration Severity Chart (see datasheet) is an excellent resource for guidance on where to set vibration thresholds. It is a well-established standard that is based on historical machine vibration data. However, machine vibration can vary based on many factors including type of machine, mounting, etc.
An alternative way to determine where to set thresholds is to use the LCD display on a DX80 Gateway or the P6 Node to calculate RMS velocity and establish a baseline for the machine. Set the threshold at 1 ½ - 2 times the baseline.
How do I calculate RMS velocity from the holding register representation displayed on the LCD screen?
Use the LCD readout for input 1 to calculate RMS velocity in inches per second. Divide the readout for input 1 by 10,000 to get RMS velocity in inches per second.
Use the LCD readout for input 2 to calculate RMS velocity in millimeters per second. Divide the readout for input 2 by 1,000 to get RMS velocity in millimeters per second.
How do I set vibration thresholds?
The Q45VT comes preconfigured with a vibration threshold set at .15 in/s (3.8 mm/s). This threshold can be changed to other preset thresholds using DIP switches (threshold settings based on the ISO 10846 Vibration Severity Chart). See data sheet for details.
Use the UCT to set vibration thresholds for the P6 and H6, and to change the Q45VT thresholds to something other than the DIP switch selectable thresholds.
How do I set temperature thresholds?
The Q45VT comes preconfigured with a temperature threshold of 80°C. To change it, or to set a temperature threshold for the P6 and H6, use the UCT.
What is the temperature measuring range of the QM42VT1?
The temperature measuring range of the QM42VT1 is -40 to +105°C (-40 to +221°F)
Can the QM42VT1 housing withstand tough industrial environments?
The QM42VT1 has a robust zinc alloy housing and is rated IP67 for demanding industrial environments.
Is the QM42VT1 rated for hazardous areas?
Does the QM42VT1 come with a node?
Nodes are sold separately. There are 3 nodes to choose from, the Q45VT, the P6 and the H6. Consult a Banner app engineer to determine which node is best for your application.
How long will the batteries last?
At a 5 minute sample rate, the batteries will last 3+ years on the Q45 and the P6 & H6 at the 250 mW setting. On the 1 W setting, the P6 and H6 will last 2 ½ years at a 5 minute sample rate. See the QM42VT1 datasheet for details.
How do I know when it is time to change the battery?
Because lithium batteries don’t lose power gradually over time, but rather maintain their power and die very quickly at the end of their life, it is not very useful to be able to check the power level of the battery. The most effective way to ensure that the battery will not die unexpectedly is to put the battery on a regular maintenance schedule based on its expected life according to the sample rate. See the QM42VT1 datasheet for details.
Is there a line powered node available?
A line powered version of the P6 node will be available in October, 2015.
How far can the QM42VT1 and node be from the gateway?
The Q45VT has a line of sight range of 1km (over 3,000 ft.), the 2.4 GHz P6 and H6 have a line of sight range of up to 3.2km (2 miles) and the 900 mH at 1 Watt has a line of sight range of up to 9.6km (6 miles). To verify range for a specific application, Banner integrates a site survey tool that displays real time signal quality results.
Can repeaters be used to extend the range?
Use the MultiHop H6 if repeaters are needed to extend the range for your application.
How many monitoring points can there be in the network?
Banner wireless networks are extremely flexible. The Simple Wire Replacement models (e.g., PM Series) can handle up to 6 monitoring points without having to use software. The Performance Series can easily expand to 47 monitoring points and the MultiHop can handle 50+ monitoring points.
Which gateway should be used for this system?
Banner offers many different gateway options. The gateway that is best for your application will depend on what else you would like to do with your wireless network. Consult a Banner app engineer to determine which gateway is best for your application.
Does the wireless network interfere with existing wireless networks?
To prevent networks from interfering with each other, the gateway and all its nodes exchange a binding code that prevents radios outside the network from communicating with the gateway (similar to pairing a headset to a phone, but more secure). Additionally, gateways and nodes are configured for multiple channel hop patterns to eliminate data collisions.
How do I collect the vibration data?
The node sends the data to the gateway. The gateway stores the data in Modbus registers. The control system can pull the data from the Modbus registers.
Can I buy one QM42VT1 and node and use them on multiple machines?
When using one QM42VT1 and node to monitor multiple machines, it is important to mount the sensor in the same place whenever a measurement is taken. To use the QM42VT1 as a “check engine light” or to collect and trend vibration data over an extended period of time, it is better to have a QM42VT1 and node for each machine that you would like to monitor.
How long can the cable be between the QM42VT1 and the node?
The cable that comes with the QM42VT1 is 3 meters long (9.8 feet). If a longer cable is needed in your application, the cable should not exceed 10 meters (32.8 feet).