DOLD solid-state reversing contactors are used where it is required to change the direction of rotation of three-phase motors, to start them softly and/or to monitor their load. Diverse diagnosis functions help to be kept always informed on the operational condition of the motor. Our devices save space, wiring expenses and cost.
Depending on model DOLD reversing contactors have either a reversing function (BH 9253 ) or a combination of reversing and current monitoring (BH 9255 ), or as in our new product (BI 9254 ) even a combination of reversing, softstart and active-power monitoring - all within a single device. There is a range of reversing contactors for motor power ratings up to 5.5 kW at three-phase 400 V available
... at a glance
Long service life by wearless switching
Improved operational reliability by integrated electrical interlock
Time-saving: easy start-up by potentiometers, independent of software
Easy overview on machine condition by diagnostics
Cost-saving: the BI 9254 can often be used instead of a frequency converter
Space-saving and easy-to-wire: all functions within one enclosure
DOLD reversing contactors - dead easily to handle
An integrated electrical interlock of the both directions of rotation ensures a troublefree and safe operation of your plants.
Exact zero-voltage switching
Switching of the semiconductors in the zero crossing of the alternating system voltage avoids EMC problems in neighbouring equipment.
No need of a very quick acting fuse
In principle a solid-state reversing contactor should be protected against short-circuit by a specific very quick acting fuse. This is to be selected on the basis of the semiconductors I²t value indicated in the data sheet. In practice, however, you can do without such a fuse. Then, the device must be protected by a commercially available motor protection switch.
Ready-to-use products for your applications
With optimized parameters such as heat sink size, EMC, heat dissipation etc. To select the product which is best suited for your application it is enough to know the current flowing through your load.
Switching of high load currents results in considerable heating of semiconductior contactors and relays. Inacceptable temperature rises may cause device failures after a time. To counteract this risk DOLD developed advanced technologies. Thanks to the DCB (Direct Copper Bonding) method it is possible to optimize heat dissipation in the power output element of the semiconductior contactors and relays and to ensure the operational reliability of your systems.
... Application areas of reversing contactors include
Extrusion and injection moulding machines
Feed devices, e.g. in wood industry
Servodrives in process technology
Sewage treatment plants
POWERSWITCH reversing contactors
zero-voltage switching with integrated electrical interlock and heat sink, top hat rail mounting