Electric motors are critical for the operation of every business, and ensuring their reliable operation is essential. Hybrid starters offer advanced motor protection for increased productivity and reliability. They have multiple functions and offer control panel builders many ways to save time and money for motors up to 4kW. Moreover, they also provide greater functionality than conventional DOL and reversing starters.
Their four key functions are forward running, reverse running, motor overload and phase imbalance/loss protection: safe shutdown to SIL3/PLe is optional. Both AC and DC control voltage options are available, and all modules have a 22.5mm wide construction.
Hybrid means they use a combination of wear-free semiconductor and contactor switching and an integrated electronic motor overload. This gives them high performance switching to AC53a, with contact life up to ten times longer than conventional contactors. More importantly, there are fewer warranty callouts due to higher reliability.
Benefits of hybrid starters
Some of the benefits are obvious and others less so. Their compact design reduces control panel size and makes it easier to install. Compared to conventional DOL starters, they are 50% smaller and 75% smaller than reversing starters. This leads to less metal, fewer busbars and less floor space and a 60% reduction in installation time. Additionally, the integrated hybrid design reduces installation and wiring time.
Reducing heat dissipation can further decrease space requirements. In the closed, confined space of a panel with airflow often limited by an IP54 rating. The sizing of the panel not only needs to accommodate the product but also its heat dissipation. A standard thermal overload relay creates heat proportional to the current, whereas an electronic one can cut that by half. Reduced heat means a more compact panel and simple ventilation.
Because the switching and overload protection is in a single module, panel installation is faster, and less wiring time and materials needed. This also means a significant reduction in design and fewer wiring faults. The interlocking of reversing pairs is from within the module. Most producers offer the choice of spring or clamp type terminals.
As an example of cost, including hardware and wiring connections, all hybrid reversing starter combinations, and all hybrid emergency stop combinations are cheaper. This does not include the savings achieved due to smaller cabinet sizes.
Hybrid motor starters offer a cost-effective solution for cabinet mounted multi-motor applications using 3-phase motors up to 4kW. These include fans, pumps and conveyors as well as machine tools and hoists. Motor overload setting is simple, requiring only a screwdriver adjustment.
Upstream protection of the hybrid devices is with either fuses or circuit breakers. Phoenix Contacts’ devices offer the option of internal fuses for type 2 coordination to IEC 60947 4-1. As an alternative, Schneider Electric provides Type 1 coordination using its GV2L breakers, or Type 2 using separate fuses. For additional savings, hybrid starters are suitable for grouping under a single circuit protection breaker.
End-users also benefit
According to Schneider Electric, about 35% of the root causes of motor failure are due to thermal overload problems. The compact TeSys H series includes advanced protection that can significantly improve operation and reduce unwanted trips by solving up to 55% of motor failures. Reduced maintenance also results from longer contact life and fewer wiring issues due to the integrated construction.
This means end-users benefit from the lower initial cost and the smaller footprint of the electrical cabinet and electrical performance. The improved reliability increases productivity as there are fewer unscheduled motor stoppages and thus less waste and scrap. Fault indication is by diagnostic/error LEDs, and trip indication and local or remote reset are standard. Also, networking options offer control and connectivity with upstream devices like PLCs, or over a network.