Hi,
I'm using a ULN2803 IC to drive a solenoid valve 24VDC throughy relay (DIN rail mountable with base) which is rated for 28VDC,10A. How can i be sure this will work? what parameters should i calculate for this? i have worked with ULN before but it was for 12VDC PCB relay and 12Vsolenoid.

 

hi,
The ULN will work at 24V without any problem.
I would require the 24V relay coil resistance needs to be specified, I would estimate a resistance of around 800 ohms.
Don't forget to connect the ULN's common diode pin to +24Vdc
E

 

yes, ULN connection COM has to be connected to 24VDC and 9th pin to GND. Resistance is not mentioned exclusively but coil current mentioned is 56mA .

 

At 24V and 56mA thats ~428 Ohms.
The ULN should be OK

 

ok thank you

 

Why use the relay? Cant the ULN drive the solenoid coil directly?