How Does This Current Sensor Close its switch?

Status
Not open for further replies.
ThomsCircuit said:
just need to know how to complete the switch E-Tech. this setup is cost effective too.
Click to expand...

The white socket.
Click to expand...

If the switch is the white connector, then when closed, it shorts to ground. And seeing that its on a separate PCB makes me think it may be some distance away from the CT circuit. So...you would remove R2, and maybe C1, then connect Q1 Drain to a relay -coil then relay +coil to +12. Connect a deenergized relay contact to your switch sensor "connector". When the mosfet turns on, the relay should energize and close the contact.

Just a reminder...
1. This is an untested circuit.
2. As other members have stated, YOU will be working with DANGEROUS VOLTAGE LEVELS (levels that could even be Fatal if mishandled). Take every precaution for safety and stay on high alert!
 
eTech said:
If the switch is the white connector, then when closed, it shorts to ground.
Click to expand...
yes it does. Ive got a few signal switching relays left that are polarity sensitive so ive used them in this circuit.
here is the modified circuit. just give it your approval. And i will be careful.
Note the 2n7002 ive located is an SMD type 7.5 Ohm 115ma 60v. The Relay is a NA-12 W-K PDF Datasheet
 
Last edited:
ThomsCircuit said:
How does the CT circuit effect the workshop circuit??
Click to expand...

Your schematic #109 has a few errors:
1. You have the +5v connection wrong. +V (+5) should only connect to the + side of the relay coil.
2. +5V for the relay (you can use 12v if you want to use a 12v relay) will need to come from your DC power supply.
3. There should be a 1N4004 (minimum) across the relay coil. Cathode to +coil, Anode to -coil.
4. The DC ground connection needs to be the same DC power supply ground used for the workshop circuit.

I think the above errors is what RonS was referring to...

Anyway, with the noted corrections it shouldn't affect the workshop circuit at all except to open/shunt the sensor switch connector pins via the relay.
 
Last edited:
OK. I believe i have this correct now.
Added (4148) across the coil of the relay
Used ground from Workshop circuit. It comes in from SW1 pin 1
Re-routed 12v to connect to just the positive side of relay coil (NA-12WK)
12v supply from SW2 pin1 of workshop circuit

--------------------------------------------
All components will be on a custom made board to fit this box.
The CT will protrude from the box on the other side of the circuit board
low voltage connections will be supplied to box via 3 pin plug from workshop circuit
Distance from each box is apx 5 inches. they are completely isolated from one another
 
Here is schematic



Simulation Results:

.step rl=12
.step rl=13
.step rl=14
.step rl=15
.step rl=16


Measurement: irms
step RMS(i(rlac))
1 9.9596 0 2
2 9.19328 0 2
3 8.55165 0 2
4 7.97648 0 2
5 7.47549 0 2

Measurement: led
step i(led)
1 0.0212006
2 0.0212007
3 0.0212014
4 1.06739e-008 <---LED off
5 1.06741e-008 <---LED off

The simulation shows the LED turns off when the AC line current falls below ~8.5 Amps.
But this is only a simulation. You'll need to test,tune, repeat, until the desired results are obtained.
 
Last edited:

Will there be any AC line voltages inside the box?
 
eTech said:
The simulation shows the LED turns off when the AC line current falls below ~8.5 Amps.
But this is only a simulation. You'll need to test,tune, repeat, until the desired results are obtained.
Click to expand...
Can you tell me if I connected the 250k Pot correctly? Best to see in the PCB. Copper pours will take care of the dangling grounds
Ive attached the SCH and top n bottom 3D renders. You can see the CT is opposite of the components. The PCB will be contained in a box and only the CT, LED, and 3 pin plug will be exposed.
C2 is a bi-polar cap 22uF 16V Radial Tantalum Capacitor


 

Attachments

  • CT-DESIGN04b1.png
    14.1 KB · Views: 253
  • CT-DESIGN04b 3D FRNT.png
    21.7 KB · Views: 252
  • CT-DESIGN04b 3D BACK.png
    16.9 KB · Views: 253

If U1-pin 2 is the wiper then it looks correct.

On C2, you might want to put a + symbol next to the positive pin so it doesnt get installed backwards (and cause a firecracker sound when powered on ).

BTW - If your using Designspark PCB...you can design your own 3D printed box with Designspark Mechanical and pass the 3D PCB from DSPCB to DSM. I did this for my last project. Had the box 3D printed and the box came out nice. I didn't have to cut or drill any holes, etc. Took a couple of weeks to learn the software though and a couple of scapped printed boxes to get it right...but it was worth it. Now its easy....
 
eTech said:
If U1-pin 2 is the wiper then it looks correct.
Click to expand...
OK In other projects i connect the wiper (2) to 1 or 3 This setup is different.

eTech said:
On C2, you might want to put a + symbol next to the positive pin so it doesnt get installed backwards (and cause a firecracker sound when powered on ).
Click to expand...
i thought these caps did not have a polarity? Im using ( bi-polar cap 22uF 16V Radial Tantalum Capacitor ) I will add the values though.


So I can make my own enclosures? Now thats cool!
 
Status
Not open for further replies.

Similar threads

G
  • Question
Replace Hall sensor with switch in Tuya door/window sensor
Replies
9
Views
3K
rjenkinsgb
U
  • Question
What type of sensor is this?
Replies
2
Views
1K
JimB
A
  • Question
Finally got my heat sensor / controller / heating element working.. now, how can I add an on/off switch?
Replies
1
Views
1K
ZipZapOuch
  • Question
How to Create a 12V Breathing/Fading LED Circuit with My Current Components?
2
Replies
33
Views
3K
Lightium
T
  • Question
switch circuit
Replies
13
Views
2K
ZipZapOuch
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…