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Servomotors with variable speed without limit and moment switches (SMiFM)
Servomotors without limit and moment switches with intelligent control (control of position, current supervision and moment control) are technically superior and more economical than traditional servomotors equipped with limit and moment switches that are controlled via contactors ( even with communication and current supervision). SMiFM for industrial fittings control (ball valves, gate valves, etc.) is providing many advantages to users, like lower maintenance cost (TCO) and higher reliability, because fittings have longer lifetime and lower service repairs requirements.
· Servomotor without limit and moment switches is considerably more economical, smaller and lighter (entire assembly of switches or even position sensor is not necessary)
· Less variant of servomotors are needed, because speed and switch-off moments are possible to set in wide range
· Possibility of setting different speed and moments for closing and opening of fittings and thus eliminate unwanted and damaging events (cavitation, hydraulic surge). Fitting can for example open very slowly in order to balance pressure on both sides and then it can speed up to open.
· When closing then from 2-5% open the speed is going to slow, in order to minimize impact on mechanical parts, especially valve seat, which is in traditional fittings continualy damaged by accumulated kinetic energy of servomotors and fitting's pull rod.
· Limit switches or position sensor is attached on fitting, these are not influenced by servomotor gear conditions. Linearity and precision of position sensor is chosen according to the application (from 0.1% for magnetostriction and from 2% for inductive sensor).
· Important servomotors (three- and two- phase) are possible to control even during power outage, through backup battery connection.
· Power cabling to servomotors is designed on smaller dimensions compared to traditional servomotors, because cabling is designed for nominal motor current.
· For applications with SCADA system and SMiFM with communication module (Profibus DP,DeviceNet,CANopen) it is advantage to store selected data from servomotor and fitting in order to supervise their characteristics and provide intelligent maintenance - maintenance is then carried out only when necessary ( change in fitting characteristics - jamming, valve damage by cavitation, etc.)
· SMiFM with communication module can provide method of supervision of state of control valves complying with functional safety requirements (SIS – Safety Instrument System).
Models:
MON 5203X
MON 5244X
MON 5222X
If you are interested in current price list, please send us e-mail: info@zpaindustry.cz
ZPA Industry Inc. is an Invensys Wonderware Registered System Integrator