help for linear control of current

[Gioia]

Hi everybody,


I would like to control the current inside the different coils. The current change slowly therefore I can model my coils as resistors. The resistances of my coils are comprised between 9-120 ohm. I would like to control the current in proportional way between 0-1A with a signal come from a data acquisition board (NI DaQ USB-6259). The data acquisition board can give me analogical signals (0-5 V) and digital signals. I would like also to switch the current direction.

Can you help me? Can you suggest some components and architecture?

Cheers,

Gioia

 

[alec_t]

Providing current proportional to a control voltage is relatively straightforward. Can you switch the direction with a manual switch, or does it have to be controlled by the DaQ too?

 

[Gioia]

No, I can't switch the direction with a manual switch because I woul like to control the movement of magnetic robot by means of joystick so it have to controlled by the DaQ (with analog o digital signal).

Thank you very much,

Gioia

 

[alec_t]

To pass 1A through a 120Ω coil will need a supply voltage of at least 120V. Do you have that? Do you need to be able to reverse that 120V?
The coil will dissipate 120W at 1A, so will get very hot. Is it rated for that amount of power?
How fast will you need to change the current direction?