B
B2.3 Process Flow Diagram and System overview
B2.1 Introduction
![]() | When you start using the VPVision as a monitoring system, good preparations are key to a successful installation. This makes the hardware and software installation easier which will result in more coherent monitoring reports. |
![]() | Be aware that the new version of VPVision has just released, for more information about VPVision 5.2 can be found in the user manual |
Get a detailed insight into the installation from:
- Relevant pictures which can be taken during the factory visit (installation points and other important details).
- The list of all of the remote I/O modules and their connection overview.
- An overview/factory map (P&ID) with all rooms, piping diagrams (CAD drawing or PDF).
- The Process & Instrumentation Diagram (P&ID) of your compressed air system.
- A clear wiring diagram for the VPVision Main cabinet and for each I/O module.
It is important that all these points have been check during the preparation phase of the system. If you have not, please do so still, as this will help determine the need e.g. converters, cable lengths, power supply needs, etc.
![]() | Important before you start: take into account the importance of proper documentation. |
Useful tools are:
- Configuration List: An easy overview of all the connected devices and their corresponding information, like Modbus address, the zero-span and converters IP address. (Downloadable documentation example)
- Overview of network architecture: A general overview of the factory’s Ethernet structure for VPVision, it’s sensors and converters. See an example here:
Here are a documentation example and generic schematic network (click on the image for a better view):
B2.2 Walk through the factory
Step 1: Prepare everything in detail to prevent surprises during installation. Do a walk through the factory.
- Check all of the installation locations of all the instruments, the remote I/O boxes, and the VPVision Main cabinet. Take into account the installation conditions as per the user manuals of the specific equipment.
- Check the location conditions, for example, watch out for potential water intrusion, excessive heat, and accessibility of the remote I/O modules.
- Check if there is mains power is available for the VPVision main cabinet and all remote I/O modules. Alternatively, check if 24 VDC. is available for the sensors.
- Mark installation distances of all the devices, so you can determine lengths of cables, and check cable routing.
- Check the pipe runs for the flow meters and take into account possible installation errors.
- Check further elements that can influence the installation and operation. Are their scissor-lifts required during installation? Is their conduit pipe needed to protect the cable and/or shield field cables? Are there specific regulations or directives for the client?
B2.3 P&ID, and System overview
Find the Process & Instrumentation Diagram and the P&ID’s of the plant if they are available.
Step 2: Get a complete understanding of the existing system, keep in mind that the possibility exists that the P&ID is not up to date, including the new measurement points.
During this step, a clear schematic of the existing system has to be made, and all of the new measurement points will have to be added to it. In most cases, the existing P&ID can be used as a starting point. In older plants, the P&ID might be missing or out of date. This is why, during the site visit, checking the existing situation thoroughly is key.
Useful for:
- Determining the location of each sensor in the compressed air system.
- Understanding the compressed air system components and their correlation, as preparation for setting up the VPVision monitoring system and the KPI’s.

Example:
Step 3: Get an overview of the system divided over the different areas and buildings of the factory.
Useful for:
- Getting an overview of the location of the sensors and to learn how to best wire them.

Example:
B2.4 Connection possibilities
Step 4: Decide on how each sensor will be connected to the VPVision main cabinet. This is an important step, as you will need to be well aware of all the possibilities and their associated infrastructure. This can have a large impact on installation costs.
The 3 most common connection options for VPVision are:
- Modbus: Directly connected or can be connected via a Modbus to Ethernet converter. Connect Modbus devices always via a daisy chain with max. of VPFlowscope’s 8 devices in a single chain, due to power and/or data limitations.
- Analog: Directly connected to a 4 .. 20 mA. or an Ethernet Remote I/O module. Each sensor has to be wired separately to an analog input on this module.
- Ethernet: Devices with an Ethernet output, like the VPInstruments VPFlowScope M, can directly communicate via Ethernet. The protocol is Modbus/ TCP.
Below we show an example project with a mix of connection types:
Legend:
Part | Inputs | Icon | Part number |
VPVision Main Cabinet | The VPVision main cabinet provides inputs for up to 8 VPFlowScope devices over Modbus and 8 analog inputs See order code for further details. | ![]() | VPV.60XX.XXX |
Modbus extension module | It provides additional power to the Modbus sensors, which may be needed when using long cable runs or when the sensor power consumption is exceeding the limit of the VPVision main cabinet. | VPA.5030.011 | |
Modbus to Ethernet converter | Converter for 8 Modbus devices, including power supply. All data will be transferred via Ethernet (Modbus TCP). | ![]() | VPA.5030.111 |
Analog to Ethernet converter | Converter for 8 analog sensors, including power supply. All data will be transferred via Ethernet (Modbus TCP). | ![]() | VPA.5030.211 |
Modbus to Ethernet + analog to Ethernet converter | Converter for 8 Modbus devices and 8 analog sensors, including a power supply. All data will be transferred via Ethernet (Modbus TCP). | ![]() | VPA.5030.311 |
VPFlowScope | VPFlowScope flow meter. Connected via Modbus or Modbus TCP (VPFlowScope M only). | ![]() | VPS or VPM |
Modbus junction box | Create your daisy chain without mixing up the different wires within the cable. | ![]() | VPA.5030.020 |
Sensor | Measures a specific unit in the system. Options could be flow, pressure, temperature, dewpoint or amps. Outputs can be analog 4..20 mA., Modbus or Modbus TCP. | ![]() | |
PC | Connect your PC to the Ethernet system or directly in order to read out VPVision. | ![]() |
So for the example at hand, this could look like this as a factory overview:

B2.5 Wiring Diagram
Step 5: Make a wiring diagram.
The wiring diagram is important, as it provides all the information for the contractors on how to install the cables and cabinets properly. When the system is in operation, it provides information on how all the components are connected and how they relate to each other.
We advise making a wiring diagram for the entire installation.

B2.6 Next step
Now that you know how to prepare for the installation of VPVision, it is important to document everything. The next step in the installation procedure of VPVision is: