Hi Sparky2003,
We had some bad experiences with the new Telemecanique oveload relays from this range. The relay uses a pushbutton to reset following a trip, and I seem to recall it has a test button too. There is a facility for resetting automatically, which is not the default option. Numerous times, we found that the relay refused to reset following trip. This fault occurred many times on new or refurbished equipment. In the end we gave up with the product and installed a Siemens part which has performed admirably, albeit at slightly higher cost.
Our distributor, and the engineer at Siemens A&D, both said that for small motors, there is not any significant difference in the thermal characteristics of two similar motors of the same rating from 'reputable suppliers' (their words) if built to the standard IEC frame sizes. Therefore the protection relays are largely interchangeable, as their characteristics are designed match the thermal behaviour of a typical motor. When questioned further, we were advised to avoid using O/L relays designed for large motors turned down to the bottom of their range, as the time constant is optimised for the larger motor.
My personal opinion is that the newer (2000 onward) Telemecanique ranges have in general shaved a penny or two off the manufacturing cost, but that the build quality has nosedived. We had practical experience of one of their newly-released ESD pushbuttons failing, after the clip-on contact block fell off the actuator head when the ESD was operated. The drive remained running. Some of the large panel builders had been notified of this design defect, but it had not been communicated to the wider electrical community. As you might guess, their pushbutton range is explicitly excluded from all our future panel designs. We have a large installed base of older Telemecanique equipment, and the older products are pretty good for the price we paid. They aren't the very best, but they certainly aren't the most expensive either. Our problems arise when the old equipment wears out and we have to replace with the modern equivalent.
Hope this helps,
