ni 9269 and RST-3-4-40

[alhabeeb]

Hi,

I want to activate a triac RST-3-4-40 [3~23 VDC, 20mA] by generating voltage by ni 9269. When I generated [1~1.99]V, it was good, but when I increased the voltage [2~10]V, the voltage dropped to [0.94~1]V!

What was the reason? How can fix the problem.

Thanks

[dkfire]

You need to make sure that the current, mA, drawn from you setup can be delivered from the NI module. 

Can the ni 9269 supply 20mA ? 

Looks like the module can only supply 10mA per channel. 

Current drive

±20 mA all channels maximum; ±10 mA per channel typical

[alhabeeb]

Thanks for your response.

I know the ni 9269 supply can only supply -/+10mA. 

[dkfire]

So you want to drive 20mA from a 10mA source?

Have you tried to use a power supply and see how much current is drawn from the power supply? 

[alhabeeb]

Thanks for your response.

Let's me start over.

I have a cDAQ  ni 9269 card generate -/+ 10V, 10mA and I want to control a triac 3V to 24V , 20mA. Can I connect two channels in parallel to increase the current? 

[GerdW]

Hi alhabeeb,

---

@alhabeeb wrote:

I want to activate a triac RST-3-4-40 [3~23 VDC, 20mA] by generating voltage by ni 9269. When I generated [1~1.99]V, it was good, but when I increased the voltage [2~10]V, the voltage dropped to [0.94~1]V!

…

How can fix the problem.

---

• You use a small relais, that only needs <= 8mA @ 10V to switch. Use this relais to enable a the current from an external power supply capable to drive your triac…
• You can also replace the relais by a transistor/MOSFET…

[alhabeeb]

• You use a small relais, that only needs <= 8mA @ 10V to switch. Use this relais to enable a the current from an external power supply capable to drive your triac…

Thanks. Is it possible to have a diagram of connection? 

[GerdW]

Hi alhabeeb,

just search for "mosfet driver for relay" to find lots of schematics…

[alhabeeb]

Like this in the attached PDF?

Thanks

Baqer

[GerdW]

Hi Baqer,

---

@alhabeeb wrote:

Like this in the attached PDF?

---

When the Crydom SSR works with just <5mA input current then yes…