Is it practically possible for pairs of relay contacts to connect at the same time? In my opinion there will always be some time difference. And it will always be the contact that disconnects/connects faster that suffers more.
I am not an assembler, so the correct answer is: I did not assemble .
If you want to ask or point something out, then bang on directly. Just be aware of what might happen and whether you're sure you're ready for it
SSRs for higher currents have the option of being mounted on a heatsink and sometimes on a heatsink with a fan, so there is always something for something....
As usual in this section, the discussion is more interesting than the first post .
I heard this information about connecting the relay contacts in series from experienced maintainers,
when I dabbled in the subject they mentioned that this extends the life due to faster disconnection and somewhat like in a quench chamber the arc spreads over several elements.
I got curious about the discussion of parallel connection and the choice of whether one is more interested in the problem of connecting or disconnecting.
From the indications I have heard, it can be inferred that series connection was used for disconnection. It can also be inferred that inductive pickups may have been doing the problems.
Let's see if we can wring something meaningful out of AI.
@ElektrodaBot EMR relays contain mechanical components that wear out during switching cycles. The relay contacts can become progressively damaged during both switching and disconnection of the circuit. For loads with high inrush current, contact sticking may even occur. Disconnecting circuits with an inductive load can ignite an arc that degrades the contact surface. Can connecting the contacts of a relay with several sections in series or in parallel extend its life? With two types of loads capacitive and inductive, which series or parallel connection of contacts can benefit? What phenomena accompany the switching operations and the series and parallel connection of relay contacts?
(...) of a relay with several sections can extend its life? With two types of loads capacitive and inductive, which series or parallel connection of contacts can benefit? What phenomena accompany the switching operations and the series and parallel connection of the relay contacts?
Direct answer to the question . - For inductive loads (e.g. motors, transformers), connecting the individual contacts in a relay in series usually extends the life because it more effectively dissipates and extinguishes the electric arc on disconnection. - For capacitive loads (e.g. capacitors, switch-mode power supplies with high input capacitance), parallel connection usually brings more benefits as it spreads the current during switching, reducing local contact overloads. - An important addition is always the use of additional quenching circuits (e.g. RC circuits, diodes, varistors) to reduce sparking and arcing during switching.
Detailed problem analysis
Phenomena accompanying switching operations . 1. switching (contact closure): - With loads with high inrush current (e.g. induction motor or capacitance) there is a strong current surge. - When the contacts make contact, sparking occurs due to electrical charges filling the air gap. - An additional effect is the bounce phenomenon (contact bounce), which can result in multiple short ignitions and arc extinction during the switching phase.
2 Disconnection (contact opening): - An electric arc is produced, the length, temperature and energy of which depend, among other things, on the type of load and current. - In the case of inductive loads, the increasing self-induction voltage prolongs the existence of the arc, intensifying contact wear (erosion and oxidation of the material). - For capacitive loads, capacitors can discharge rapidly through the small gap between the contacts, generating sparking and accelerating contact surface degradation.
Serial contact connection . Operating principle - Several contacts in the main circuit disconnect the circuit at several points at once. The arc splits at multiple points, resulting in reduced energy per contact. 2 Advantages - Particularly advantageous when disconnecting inductive currents - breaking the arc into several smaller arcs allows it to be more easily extinguished. - Potentially slower wear of a single contact, because the arc energy is spatially distributed. 3 Disadvantages - Increase in the resultant resistance of the entire current path (series increases the number of contact points). - With capacitive loads it does not help to limit the inrush current and can increase sparking problems. - Requires some synchronisation and equal contact pressure across all contacts - the difference in their switching times can throw all the arc energy onto one contact and offset the advantages of the circuit.
Parallel contact connection . Operating principle - Current flows through several parallel paths, theoretically distributing evenly over several contact sections. 2. advantages - Smaller current load on a single pair of contacts, which helps with high inrush currents or current pulses (e.g. when charging capacitors). - Reduction in resultant resistance, beneficial for applications with high continuous currents. 3 Disadvantages - Uneven current distribution (even small differences in the resistance of individual tracks can cause one contact to be more heavily loaded). - When disconnecting an inductive circuit, the arc can focus on the contacts that will unseat first. As a result, only one of the contact pairs can be destroyed. - The arc is not stretched as effectively during the disconnection phase as in a series connection.
Supporting explanations and details . - The arc phenomenon is central to contact degradation. The high temperature in the arc region melts the surface layer and produces metal microspheres that can stick to the opposite contact, causing unevenness or even sticking. - By engaging additional quenching elements (e.g. diodes, RC circuits, varistors), the arc energy can be reduced. For DC or highly inductive circuits (e.g. solenoids), free-wheeling diodes or RC snubbers mounted in parallel to the contacts are often used.
Practical tips . 1. for inductive loads - Consider connecting the contacts in series to help effectively extinguish the arc. - Introduce a suppression circuit (RC or diode) to limit self-induction surges. - Check the relay's category of use (AC-3, AC-4, DC-13, etc.); in some critical applications, a contactor may be a better choice.
2. for capacitive loads - A parallel contact configuration can reduce the surge on switching by sharing the capacitor's instantaneous charging current. - A pre-charge resistor (known as an inrush current limiter) or an NTC thermistor can be used to mitigate the current surge. - Pay attention to the total capacitance and switching frequency, as even small discharges on disconnection can damage the relay over time.
3 Universal advice - Avoid exceeding the catalogue parameters (current, voltage, switching frequency) and always leave a certain reserve of switching power. - If switching cycles are very high or currents are above average, consider solid-state relays (SSRs) or contactors with a quench chamber. - In mixed applications (both inductive and capacitive nature), a parallel and series combination of contacts (if the relay allows it) including quenching circuits may be the optimal solution.
Summary - Connecting contact sections in series in a relay aids more efficient disconnection of inductive loads by dividing the arc of electricity into several points. - Parallel connection is generally more effective at high switching currents (e.g. capacitive loads), allowing the surge to be better distributed over several contacts. - In practice, the life of a relay is determined by many factors: the type of load, the switching frequency, the presence of quench circuits and the design of the contacts themselves (material, springing, category of use). - It is advisable to supplement the contact configuration with arc energy limiting elements (RCs, diodes, varistors) in order to significantly increase its lifetime.
Questions for user . - What current and voltage does your circuit operate at? - How often and under what conditions (e.g. temperature/environment) is the relay switched? - Is the load purely inductive or purely capacitive, or are we dealing with a hybrid (e.g. a motor with a power supply system of considerable capacitance)? - Is it acceptable to use additional suppression elements (e.g. RC snubber, diodes, varistor)?
The answers to these questions will help to clarify which approach - series or parallel (or perhaps a combination of both) - will be most beneficial and how to effectively extend the life of the relay in a particular application.
You can call me in any topic by writing @ElektrodaBot. Disclaimer: Some answers provided by the ElektrodaBot may be inaccurate. Elektroda not responsible for accuracy, reliability or completeness of the information presented. All ElektrodaBot responses should be verified by the user. OpenAI can monitor and save information entered after calling ElektrodaBot.
Quite good AI combinations, even RC extinguishers were mentioned, as were contact reflections. Sensibly pointed out disadvantages of serial connection. Plus the relay application categories.
We don't wash every day and we don't wash every day. For years we have switched off the washing machine and dishwasher with a switch installed in a box under the countertop in an invisible place. The ELGOTECH ŁKD-2N-1 does the job.
When I was still a kid, I made my parents such a switch under the washing machine. Their old Amica still works to this day. I've already replaced the bearings, cupboards, heater and door lock. It doesn't want to rust it and it's worth repairing because the parts are cheap. I wonder how old it is . I currently have had the LG for 5 years and it is already rusting.
.
"Combs" is the only accurate description I know of how GPT works. After playing with it for a few hours, I found the mechanism professionally useless in technology as factual support. He mixes facts with nonsense, allows himself to be stretched on questions with a thesis, If he doesn't know something, he just makes it all up. The most important thing is to give the impression that he knows everything and has a factual answer to everything, the rest is silence.
GPT is good for coding instead. No wonder, because programming is not knowledge but a technical algorithmic (monkey) skill. So writing a piece of something in some language we don't normally know - there is real support here.
You've heard of newag cleaning machines that have a service life of 250 hours and compulsory maintenance. After 250 hours it shuts down and that's it. I switch off all the electronics in the house..... except the kitchen. This gives tangible benefits.
Have you heard of newag cleaning machines having a service life of 250h and compulsory maintenance. After 250h it switches off and that's it. I switch off all the electronics in the house..... except the kitchen. This gives tangible benefits.
. I can't imagine the manufacturer switching off my machine during production. I also can't imagine setting the clocks in the equipment every day and waiting for the android on the TVs to start up.
Introducing 'weak links' or software forcing 'service' into machines and equipment is a typical ploy of many manufacturers today. I do not think it is possible to completely avoid being confronted with such situations. Hence, it is my assumption that we have this reality and such situations are unavoidable. You don't have to look far - yesterday my printer stopped printing because the meter "came to the conclusion" that it needed to replace the toner. Of course, it doesn't need to, because it could still work, but.... Marketing has planned it that way, so the average user of the equipment will simply buy new toner. This is just one of the typical situations where a manufacturer deliberately disables a tool or machine during production .
SSRs have the advantage and at the same time the disadvantage that they are semiconductors, and every semiconductor has a breakdown voltage. Using an SSR removes any electrical isolation in the event of an open valve. It is simpler to use a suitable NTC+ relay in a surge current resistant design. The relay itself does not wear out to the extent that it matters.
>>21446349 .
Or, for example, in Motorola phones, where the 'AI' learns charging patterns and, with a regular lifestyle, charges a phone plugged in at night to 80% and recharges the tip just before getting up.
I for one would be wary of switching off a TV or set-top box non-stop - the current surges when plugging it in - I'm more concerned about whether that would shorten the life than being constantly plugged in.
Many battery-powered devices use various methods to extend the life of the cells = to protect them from user stupidity. This is usually decent equipment. On the other hand, there are devices (mostly Chinese) competing with destructive charging speeds, to the delight of the unwitting owner. This is exactly the same as racing to megapixel cameras while using 'lenses' with an order of magnitude inferior resolution and other optical properties that cause the bottom to squeeze with grief.
Mobali wrote:
This is just one of the typical situations when during production the manufacturer intentionally disables a tool or machine
The printer for the Kowalski, often cheaper than the toner for it, is not a good example. It's a foregone conclusion that buying a machine that only makes money when you buy consumables and service it will. There's a reason why car companies give multi-year warranties - you make more money on forced servicing than on the car. At least until pandemi, this was the case.
Personally, I have not encountered a professional machine that stops definitively because of some counter.
Personally, I have not encountered a professional machine that stops definitively because of some counter.
EDM machines do this when the maintenance time counter is blatantly screwed over (yes ~2.5x and this is an undocumented feature) and one day fail to start with a Christmas tree of falsely serious errors about the death of the hardware. They just don't give themselves power on e.g. generator .
The service itself has admitted that this is to persuade you to just call for a service call before you make an overhaul of a linear bearing in a somewhat precision machine.
It's not a failure, and it's easily undone by manually resetting the counter and powercycle, but I personally block the operators from doing it, because the greedy @#$%& never let go of cutting out 0.5 workpieces (that's how long it takes for an automatic lubrication cycle, started with a single MDI command, or a button on the HMI).
And so once every couple of weeks he has to let that cycle go, because he pretty much won't make any money, and it will appear that it is only out of greed that there is machine downtime - and problem solved.
The discussion centers on strategies to extend the operational lifespan of electronic devices amidst cost-cutting practices that often compromise quality. Participants share various methods, such as using extension cords with switches to eliminate standby power, employing mains filters to mitigate current surges, and modifying power supplies for better longevity. Concerns about planned obsolescence and software locks that limit device functionality are highlighted, with suggestions for manufacturers to allow battery life extension by limiting charging. The conversation also touches on the importance of maintaining devices in continuous operation to prevent damage from power cycling, particularly for certain appliances like printers and TVs. Participants emphasize the need for quality components and the impact of inferior materials on device durability. Summary generated by the language model.
.
. I currently have had the LG for 5 years and it is already rusting.
.
