Electromechanical Relays - Insights

1.High thermal rating for the winding wires. 2.Bi-metal contacts in place of silver contacts. 3.Mild steel components in place of the nickel iron (like armature, yoke and core) with better and innovative design. 4.Simple approach of the coil design for the induction coils for the Electrical reset relays. 5.Innovative and indigenous design for the flags.

Especially for high end applications, overall size, high reliability switching applications necessitates hermetic seals which in turn calls for utilizing laser weld technologies. Also test requirements such as vibration,shock,fine leak tests,automated test equipments are requirements for MIL grade relays.

MEMS, MEMS, MEMS. It is the only new thing in the world of EM relays in decades. They will replace most EM relays, I expect, within 10 years.

OMRON and XCOM are making MEMS devices. Coto has done a good job of cost reducing and miniaturizing reed relays. I don't see much out of the other suppliers that is all that successful, as the surface-mountability and RF performance of true EM relays is still pretty bad for anything in the tens of dollars range.

Power Plants and Oil and Gas companies are creating the most innovative electromechanical relays.

GE and Cutler Hammer are still making Electromechanical protective relays.

We are supplying the relays for all automotive applications -- flasher, wiper, radiator fan controls, grid heaters etc Industrial segments -- CMRs, for protective relays etc Consumer segments --UPS, stabilizer Defense ,Telecom & power conditioning equipments

As safety component for audio speakers, with retarded switch-on. As safety component where the power circuit had to be physically remote from the low voltage circuitry; As a current amplifier.

Buffer between plc outputs and load, Built some relay logic controllers, Latching functions in power on off control, Safety functions

Pretty clever stuff right now in radar and comm instrumentation, although it's not crazy new, it's just that we are implementing things everyone talked about 5 years ago as being some sort of fantasy. Everyone is moving to reconfigurable matrices or load boards, with the same pure digital synthesis test system pretending to be whatever is needed. This is why the linearity of EM is still king, because both radar and comm is pushing linearity requirements due to clever waveform and bit stacking far more than has ever mattered before.

1.To represent the various Make and Break contacts for the circuit breakers and thereby reduce the cost of cables run between the control panel, breaker panel and yard.

In Hybrid or CNG vehicles relays are used for cutting all electricity while fuel filling.

Most disasters are associated with hot switching parts due to bad test engineering. Higher speed testing and switching happens a LOT in the time scale of human reactions. You can blow out a whole stack of load boards in a few seconds if you're clicking away at a kHz with a negative pulse instead of a positive pulse. OVERLAY YOUR WAVEFORMS. CHECK THEM TWICE (with a different person, if possible)!

Improper use of the technologies and design with inadequate knowledge of the application requirement of the aux and trip relays. For e.g the coils of the trip relays will have to be designed carefully with respect to the individual voltage rating. Also the burden of the circuit breaker trip coil will have to coordinate with the coil rating (low burden or high burden)

We required an XOR relay and selected one from the data available to us but found that its operation is not exactly correct to our requirement.

RF with true performance to 12 GHz at least. Surface mountability with a decent RF transmission line. Faster speeds so they cut down on test time. Graceful or recognizable failure mechanisms. Easy board-rework so down time on ATE systems isn't so devastating to the bottom line (30% down time right now for SMA-type switch matrix systems, that's ridiculous).

1. Cost reduction with innovations. 2. Fast and consistent operating time for the trip and aux relays. 3. Safe and fool proof operation of the relays and flags.

Super multi compact relays, high power/ current and electronic design, easy repair and replace parts.

Look at RF MEMS parts, they're real now (finally). Be careful of definitions of open and close time. Make your own linearity measurements if you are doing cutting edge waveforms, because stuff that didn't matter 10 years ago is a system killer now.

Most brands are getting better and more reliable; stay with a locally stocked one because you may have to replace it [Sd D].

Quality should be given more importance rather than cost considering long term maintenance free services.

Do not exceed the specifications and try to find out how they influence life time.

Digital relays cost significantly less and are usually capable of doing more.

Look into the design of the contacts and coil standards.

Double the contact rating above your expected load.

Yes for the solid state electromechanical relays

Check the relay characteristics

Switching current

Buy enough parts to last your build. The smaller chip-scale packaging on MEMS and reeds is changing fast enough that if you do a design in, you might be left "less supported' a year down the road. Qualify and get your parts. . . don't trust sales and marketing guys about what/when the next gen part is, and definitely don't wait for it.

While selection and usage of the electromechanical relays various aspects like 1. Consistent timing in operation. 2. Simple design and ease of understanding of the product by customers. 3. Versatility and compactness of the contacts and the coils. 4. Aesthetics and simplicity for the mounting on the control panel.

Yes, please do not used unbranded electronic / electrical components, using of local component will put your life in danger.

Ensure operating times and characteristics are indeed what the situation requires prior to ordering / purchasing.

Operating voltage, voltage stress, contact tip design, mechanisms, also the life expectancy.

While selecting relays consider the inrush currents also in addition to load currents.

Watch contact rating [current]. Remember they produce heat in the cabinet.

Prevent under sizing, never use above 2/3 of specified load.

Buy robust units. Do not be cheap.

Verify contact ratings are correct

Check the relay specification

Check for diode protection

Yes for long operation

As in 8.