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Can I directly do this type of switching in my inverter circuit?

This won't work. As soon as the Solar Panel doesn't provide enough power to keep the relais switched on, the relais will fall off, connect utility power which will flow trough your load and the coil ...
kruemi's user avatar
  • 3,539
2 votes

Designing a Circuit to Connect and Disconnect a Load to a DC-DC Converter @3 MHz

When switching at 3 MHz you can't use a relay but, to decide what might be suitable requires a stronger definition of what performance needs to be. For instance "ON" needs to be stated as a ...
Andy aka's user avatar
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1 vote
Accepted

Normally closed relay failing due to shock and vibration

There do exist relays rated for high shock and vibration. They are a lot more expensive, but they do exist. Depending on the country you live in, you might have some difficulty getting your hands on ...
Chintalagiri Shashank's user avatar
1 vote

Can I directly do this type of switching in my inverter circuit?

No you cant do that. At night electricity flows from the 12V through the lamp and the relay coil causing the relay to buzz or chatter. Changes, well everything, add diodes on the solar output so that ...
Jasen  Слава Україні's user avatar
0 votes

Normally closed relay failing due to shock and vibration

Consider a latching relay Only uses power when changes state Perhaps with a monitoring line to ensure correct operation Albeit with extra code complexity If your application will permit it, you ...
jonathanjo's user avatar
0 votes

Normally closed relay failing due to shock and vibration

You could characterize the shock and vibration and choose a relay accordingly. Even from Omron, I wouldn't expect much from a $1.66 part to begin with so there's definitely room for improvement there. ...
vir's user avatar
  • 20.4k
0 votes

Switch between two DC sources using Schottky diodes

Lithium batteries are very fussy - they require very precise control of current & voltage during charging, and each cell must be individually managed so you need the BMS. I suggest consider using ...
Fabio Barone's user avatar
  • 5,452
0 votes

Using a Relay to control an irrigation valve solenoid

Most of your thinking is correct, but - There still will be an open circuit as the armature breaks the NO contact and travels to the NC contact. If you want to really suppress the arc, leave the ...
AnalogKid's user avatar
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1 vote

driving 24V relay from 3.3V controller

Forgive me if I misunderstood you, but it sounds like you expect the relay to transfer something to its "output" when it activates. This is not going to happen (unless you connect the switch ...
Simon Fitch's user avatar
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1 vote

12 V relay buzzing/fast clicking sound when getting signal from Arduino UNO

You need a ground wire from the Arduino to the relay module. (This has already been mentioned and didn't completely fix the problem.) Power the relay module from 5V instead of 12V. The relay have a ...
JRE's user avatar
  • 72.6k
0 votes

12 V relay buzzing/fast clicking sound when getting signal from Arduino UNO

You need to connect a ground wire from the Arduino to the ground of the relay board in addition to the IN1 wire you already have connected such that they are working from a common ground potential.
EricEverton's user avatar
0 votes

driving 24V relay from 3.3V controller

It doesn't look to me that there is any voltage to measure- you should have an open circuit between COM and NO with the relay de-energized (no continuity) and a closed circuit (continuity) between COM ...
Spehro Pefhany's user avatar
3 votes

driving 24V relay from 3.3V controller

You are measuring across the normally open contacts of the relay, when the relay is activated they are connected together so they are a short circuit. The voltage across a short circuit should be zero....
GodJihyo's user avatar
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0 votes

Esp32 controls a 12v coil relay through PC817 and 2N7000

U1 is redundant; simply choose a MOSFET suitable for logic-level drive. BSS123 is a typical choice, or shop around for others with suitable ratings, including whatever current the relay coil needs. ...
Tim Williams's user avatar
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1 vote

Esp32 controls a 12v coil relay through PC817 and 2N7000

Looks okay, except D2 is backwards. It would be better graphically to show it in parallel with D1, the downward arrow for a positive voltage is against convention. I think I'd like to see a bit more ...
Spehro Pefhany's user avatar
0 votes

Esp32 controls a 12v coil relay through PC817 and 2N7000

D2 will never light. If it should works as "ON" indicator you have to swap its direction. Current to PC817 IR LED will be about (3.3-1.0)/1k8=1.28mA. In worst case current transfer ration of ...
Michal Dudka's user avatar
1 vote

Troubleshooting and understanding single coil latching relay circuit

The Amazon listing uses flip-flops and non-latching relays to achieve a "latching effect"; remove power to the board and the relays revert to their unpowered state. I would argue that a ...
vir's user avatar
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2 votes
Accepted

Troubleshooting and understanding single coil latching relay circuit

Based on the module image JQC-3FF-S-Z are not latching relays. The control circuit uses trigger to change the state. Could you please describe a task that you are trying to solve. I used to drive ...
zoonman's user avatar
  • 182
1 vote

Troubleshooting and understanding single coil latching relay circuit

It appears to me that the relays are normal non-latching DPDT relays, with the toggling function produced by the six pin ICs by each relay. In that case,the relays WILL go to their NC position when ...
Peter Bennett's user avatar
2 votes

Automotive 12 V relay setup with push button switch and multiple devices

Add a limit switch so that the latch motor can only operate when the lid is fully closed.
Jasen  Слава Україні's user avatar
1 vote
Accepted

ULx200x V.S. SN7546x

SN7546x is a higher voltage version of the ULN200x (100 V vs. 50 V), otherwise they're pretty much the same. They are neither TTL nor CMOS, they are bipolar Darlington arrays. Note that both the ...
GodJihyo's user avatar
  • 25.1k
1 vote
Accepted

Is it possible to use just two SPDT relays to control this AC motor?

The application would require two single-phase, 110 V ~, 12 A, AC-7B duty, modular contactors with 24 V DC coil and (1 NO + 1 NC) contacts. Here's the schematic. The limit switch is not shown.
vu2nan's user avatar
  • 18.9k
2 votes

Is it possible to use just two SPDT relays to control this AC motor?

I don't think your schematic is right- the top switch would do nothing. Something like the below is what I expect could work (limit switch(s), thermal protection etc. not shown): simulate this ...
Spehro Pefhany's user avatar
0 votes

Arduino and Pololu Motor Driver Shield Undervoltage Issue When Driving Relay and Motor Pump

I found out what the problem was, despite me cutting the trace on Pin 8 of the Motor Driver Shield like the website mentioned (in order to decouple Pin 8 of the Arduino from the Shield), whenever md....
Nathan Nguyen's user avatar
1 vote

Use of TX/RX on Wemos Relay Shield

The shield simply has the standard names at all its pins coming from the MCU. It does not necessarily mean that there is something connected in the shield. The schematic of, for example, the D1 mini ...
the busybee's user avatar
  • 3,389
1 vote

Why is the Relay "Chattering"?

When your load is applied the measured voltage will drop a bit (or maybe a lot) so you can get chattering as a result of that. So it's important you have adequate hysteresis for the lower trip point. ...
Spehro Pefhany's user avatar
0 votes

Why is the Relay "Chattering"?

Seems you need what is known as a "window comparator". This is just two separate comparators, each looking at the same input signal and comparing it to separate thresholds, Vlow and Vhigh. ...
Fabio Barone's user avatar
  • 5,452
0 votes

Use of TX/RX on Wemos Relay Shield

The relay is triggered by one single pin - but you can select which one by cutting tracks and soldering to select which one you want. These are called solder jumpers. However the TX and RX are not ...
Justme's user avatar
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0 votes

Use of TX/RX on Wemos Relay Shield

... I am curious of the use of the TX/RX pins for this component. The RX/TX pins are not populated. There is no usage of them. There are also I2C and SPI pins so is serial communication possible ...
Colin's user avatar
  • 734
0 votes

Use of TX/RX on Wemos Relay Shield

Did you look at the internal schematic? That was on the link you posted. Here's what it is. If this is accurate, then it looks like all of the input pins are tied together and just connect to the ...
SteveSh's user avatar
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