Perfect for large installations and machines, Asco/Joucomatic's new Valve Connection System links actuators together in an easy, quick and economical way
Asco/Joucomatic introduces a connection system for actuators and solenoid valves. The Valve Connection System, VCS, comprised of a connector for each valve/actuator, a 2-wire profiled cable (the VCS line) and an interface, links actuators together in an easy, quick and economical way. The VCS is perfect for large installations and machines as up to 127 connectors for spool valves with two solenoid coils each (bistable valves) and up to 254 sensor inputs can be connected with a single cable, spanning a length of up to 2.5 km.

Automatic feedback of the control signals provides for a high degree of data protection.

With the VCS all types of valves (pneumatic valves, hydraulic valves and general purpose valves - water valves, gas valves, oil valves etc.) can be connected together.

Furthermore, spool valves can be used in the VCS individually or several can be linked together to form valve manifolds.

Fieldbus systems (eg Interbus-S or Profibus-DP) are used more and more in installations and machines to connect inputs and actuators to a controller (PC or PLC).

The VCS has been designed precisely with this in mind.

The VCS interface acts as a communication centre for a PLC, a field bus and up to 127 VCS connectors.

In a loop structure, data from the field bus passes through the interface and is transmitted to the valves via the VCS line.

The corresponding feedback from digital inputs (limit switches) is transmitted over the VCS line to the interface and from there to the fieldbus system.

All valves and actuators with their VCS connector are referred to as participants.

These participants are connected to each other and to the VCS interface over a 2-wire profiled VCS cable which supply them with electric current and data.

Each VCS connector fitted onto a valve is clamped onto the 2-wire profiled VCS cable.

When the lid of the connector is closed, the vampire-type plug automatically enables immediate contact with the wires of the VCS cable.

The participant is connected.

No tools are needed to fasten the lid.

The VCS system eliminates the need for cable stripping or fastening.

Each VCS connector is equipped with a data repeater valid for a distance of up to 20 m between two valves.

In addition to the technological features such as automatic cutting and vampire-type plugging, all the electronics used to extract data from the valves and to transmit input data from the sensors are integrated in the VCS connector, thus rendering it intelligent.

This is due to a newly developed, economical, compact-sized, ASIC electronic component at the heart of the VCS's electronic system.

The standard version of the VCS interface includes a VCS power pack.

Depending on the number of valves in the loop and its size, additional VCS power packs can be clamped directly onto the VCS cable to provide for appropriate power output and to compensate for any eventual voltage drop.

In order to ensure maximum transmission protection, the VCS line is structured as a loop, with the last valve in the line connected back to the VCS interface.

The advantage of a loop system is that the data transmitted is then fed back to the VCS interface and analysed.

The output is switched only after the transmitted data and the feedback data are fully compatible.

Faulty data blocks are thus detected and the transmission is repeated.

The valve actuators only operate when the transmitted data and the feedback data are verified as being the same.

The loop structure provides for automatic addressing: each valve is automatically recognised by its position in the loop.

As time consuming manual addressing is unnecessary, double assignments are thus avoided.

The VCS system's 'brain' is its interface which controls data transmission from the fieldbus to the VCS line.

In accordance with the fieldbus system used, the VCS interface is equipped with a corresponding fieldbus module.

These modules are available for standard protocols, such as Profibus-DP, Interbus-S, DeviceNet, etc.

Data for each participant in the loop is transmitted over the VCS cable in the form of a differential signal.

A complete data cycle is processed within approximately 3 milliseconds via the protocol and 127 connectors.

Each VCS connector has an auto-diagnostic feature enabling error indication.

As a result low voltage, overheating and short circuits can all be detected.

The VCS interface also has comprehensive error analysis function with LEDs to display status and error of the fieldbus system or the VCS line, as well as the address of a faulty valve connector.

Furthermore, the VCS interface is provided with a RS-232 interface which can be connected to a PC.

Even without a fieldbus, the system can be started up and analysed with the display software provided.

The following functions are activated via a PC: valve output setting, reading of sensor input and analysis information, verification of the configuration.

The output current is limited to 100 mA per valve coil.

All valves with a 15 mm connector mounting surface and 2 watts max can be directly supplied.

In order to supply valves with higher power ratings, 15 mm x 22 mm adapters to DIN 43650 B and 15 mm x 30 mm adapters to DIN 43650 A are also available.

Power is supplied to the VCS through the standard VCS cable and an additional power cable.

Contact of the power cable is established with the vampire-type plug when the lid of the connector is shut.

The VCS connector is supplied with a second cable (24 V), intended mainly for valves with a higher power consumption.

Power up to 1.0 Ampere (24 watts) are thus available for valve outputs.

The power cable offers another advantage.

Valves can be disconnected with an emergency switch.

The inputs, however, are still supplied with power through the VCS cable and transmission of the input status to the VCS interface remains uninterrupted.

This power cable allows the scope of application of the VCS to be extended to almost any standard valve in pneumatic and fluid control technology.