USB-6009

[Hatemaboud]

 Hi

I use USB-6009 to run some motors and pumps, the digital output  gives 0 or 5 Volts so the motor will run or stop, the issue which faces me is I get this 5 volts only when the wire which is connected to the digital pin is free i.e. when the wire is not connected to the relay, but when it is connected to the relay I get only 0.7 V, any explanation! any suggestions! 

I tested my relay using the ground wire from  (32) and the 5 Volts wire from (31) and it works; I get 5 Volts whether the wire is free or it is connected to the relay.

Please see the attached drawing it could give a better explanation. 

[GerdW]

Hi Hatemaboud,

with such problems it is usually best to read the manual!

There is a huge difference between a (TTL-compatible) DO pin and the "+5V" pin of the USB6009: their ability to drive a current. The "+5V" is limited to 200mA, but the DO to just 8.5mA. Your relay surely draws a current in the order of 100mA.

Again: RTFM!

[crossrulz]

You need a buffer circuit of some type that can supply the current you need.  A simple 2N2222 might just do the job.  You will need a separate power supply.

[RTSLVU]

Here are some simple ways to control your relay with a USB-6009. Now I made these diagram for another post that wanted to operate LED's from a 24v power supply using a USB-2009, but the idea is the same. The only difference will be the resistor values in the transistor circuits, but as you can see using an open collector inverter IC is by far the simplest soultion.

[arteitle · Accepted solution]

If you're looking for a premade solution for boosting your output current capacity, you should be able to use these DC output modules (the red ones, model IO-ODC-60😞 http://www.power-io.com/products/oac.htm

I've also seen the same ones sold by Schneider Electric (as model SSLM1D23BD): https://www.eurotherm.com/products/power-control/zelio-solid-state-relays/SSLM-Output-Modules

Octopart shows them available from a few electronics suppliers, but in the past I've gotten them from McMaster-Carr: https://www.mcmaster.com/#8299k12