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New TTL relay board causing 7V on outputs...

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Hey guys

After some power issues that fried my 2x 8 channel TTL relay boards I got some replacement 4 channel boards but found something very strange once they were plugged in.

I tested the Masso outputs and they are fine (5V when low and 0 when off)

When I plug in the inputs to Masso's outputs I find the Masso now put out 7V and no change when set to high or low on the settings page. I disconnected the outputs and the Masso is back to 5 and 0 volt... I tried a second 4 channel board but the same thing. Tried the next line of outputs on the Masso and same thing?!

They are designed for Arduino and all specs look identical to what I had. See below

"This modules contains 4 relays, rated at 24V and 10A. Each relay has a LED indicator. It can be used to control various appliances, and other equipment with large current. It can be controlled directly with 3.3V or 5V logic signals from a microcontroller (Arduino, 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic). Each relay has an Optocoupler, providing optical isolation. Each relay also have a freewheeling diode protection. This module has a 6 pin header(standard 2.54mm pitch) for connecting power (24V and GND), and controlling the 4 relays. These pins have the following functions:

  • IN1 to IN4: Controls relays 1 to 4, active Low! Relay will turn on when this input goes below about 2.0V
  • GND: Connect 0V to this pin. Is used to power the board (optocouplers and relays)
  • VCC: Connect 24V to this pin. Is used to power the board (optocouplers and relays)"

Does this mean there is some resistor on the new that is causing the issue?

 

Cheers

Mitch

Uploaded files:
  • mod-relay4-24v-10a_y43NmF_x4N_ll.jpg

Hi Mitch,

It sounds like the relay board you have has pull up resistors built into it. If you measure the voltage between Gnd and IN1 and you see voltage there then the board is not compatible with Masso. Maybe removing the Link will help. I think some of the boards allow you to split the circuit in two and changes the way the input behaves but it needs to be wired differently.

There is more information about it here:  https://www.masso.com.au/forums/topic/ttl-outputs-relay-module-problem/?part=1

The relay should turn on when it sees a 5 volt output from Masso not when the output goes low.

Cheers Peter

 

Quote from CNCnutz on May 23, 2020, 1:47 pm

Hi Mitch,

It sounds like the relay board you have has pull up resistors built into it. If you measure the voltage between Gnd and IN1 and you see voltage there then the board is not compatible with Masso. Maybe removing the Link will help. I think some of the boards allow you to split the circuit in two and changes the way the input behaves but it needs to be wired differently.

There is more information about it here:  https://www.masso.com.au/forums/topic/ttl-outputs-relay-module-problem/?part=1

The relay should turn on when it sees a 5 volt output from Masso not when the output goes low.

Cheers Peter

 

disconnecting the jumper just stops the relays activating so I think it is just cutting the 24V line that activates the relays. Haha that was my original post from a while ago. I read through it again but don't know if it helps with this relay. I got lost with the wiring diagram as I am not that techy unfortunately. If it says it works with both 3.3V and 5V TTL why would there be a resistor or something causing the voltage to jump up when connected? when i ground the inputs going into the relay they activate so they work on 0V but something is causing the Masso to respond and bump the voltage up. What i find strange is that there is no change in that voltage when I set Masso to low or high. I would have presumed it would at least drop some voltage?

Cheers Peter

Mitch

Quote from CNCnutz on May 23, 2020, 1:47 pm

Hi Mitch,

It sounds like the relay board you have has pull up resistors built into it. If you measure the voltage between Gnd and IN1 and you see voltage there then the board is not compatible with Masso. Maybe removing the Link will help. I think some of the boards allow you to split the circuit in two and changes the way the input behaves but it needs to be wired differently.

There is more information about it here:  https://www.masso.com.au/forums/topic/ttl-outputs-relay-module-problem/?part=1

The relay should turn on when it sees a 5 volt output from Masso not when the output goes low.

Cheers Peter

 

They just about look identical... It's just the jumper that's different but the first relay was 5V and the second 24V...

Any more ideas?

Uploaded files:
  • InShot_20200523_181728497.jpg
  • 20200523_181409.jpg

Mitch,

Peter asked but you didn't reply to his question

 If you measure the voltage between Gnd and IN1 do you see voltage there?

Regards,

Arie.

Quote from Breezy on May 23, 2020, 6:31 pm

Mitch,

Peter asked but you didn't reply to his question

 If you measure the voltage between Gnd and IN1 do you see voltage there?

Regards,

Arie.

Didn't see a question there but I did check voltage between ground and the input and yes there's voltage. How's that possible when the relay says it's 5v low 0V high.. I don't follow this, the relay looks the same in all components and the circuitry is so simple. What am I missing?

Hi Mitch,

When you invert the Output you will find that when you turn the output off it will go high and you will measure 5 volts  and when you turn the output on it will measure 0 volts. Basically the opposite of that you had before.

At the risk of sounding like a salesman, have you seen the new Masso relay? It is designed specifically to work with Masso TTL outputs and runs on 24 volts.

If your relay module inputs have a voltage on them then they are not suitable for Masso TTL ouputs.

If you want to figure out what is happening with the relay module you will need to draw out the circuit. It will probably be obvious when you see it.

Cheers Peter

Quote from CNCnutz on May 23, 2020, 7:48 pm

At the risk of sounding like a salesman, have you seen the new Masso relay? It is designed specifically to work with Masso TTL outputs and runs on 24 volts.

Sorry to interrupt, can it be purchased in the UK? 3DTEK don't have it listed on their site so I'm currently looking to get this one: https://www.ebay.co.uk/itm/124071542735

Quote from CNCnutz on May 23, 2020, 7:48 pm

Hi Mitch,

When you invert the Output you will find that when you turn the output off it will go high and you will measure 5 volts  and when you turn the output on it will measure 0 volts. Basically the opposite of that you had before.

At the risk of sounding like a salesman, have you seen the new Masso relay? It is designed specifically to work with Masso TTL outputs and runs on 24 volts.

If your relay module inputs have a voltage on them then they are not suitable for Masso TTL ouputs.

If you want to figure out what is happening with the relay module you will need to draw out the circuit. It will probably be obvious when you see it.

Cheers Peter

The relay I had before was off at 5V and on at 0V. This new board when not plugged into Masso is the exact same. 0V turns them on and 5V off. That is why I am confused how it is different. The only difference I can see is the relays on the old unit were 5V and these are 24V. I am using the 24V and ground from the Masso to power the board. the 7V i recorded was between output 1 and ground of the board. When nothing is plugged in to the relay board I get 21V between its ground and input 1. Not sure if that is right but I have a couple spare relay boards I can sacrifice if anyone has a mad idea to try?

I was going to buy the Masso relay but $100AUD shipped was a bit steep for 6 relays when many of them are just switching 12V to energize more relays switching 230V. I had a G2 that had relay outputs already but the G3 removed them so I'm already double switching and didn't want to pay $300 worth of relays to switch more relays if you follow.

@cncnutz

So I may have a buggered Masso...

Just thought I would try the "dead"  5Vrelay board I had working for the past few years off the the Masso and it is working fine just as the new ones do. The Masso wouldn't trigger any of the original board once I put it in. With a multi meter I checked the Masso outputs and it went 4.98V when off and maybe 0.31v when activated but is there a chance there is a problem with the Masso? @masso-support

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