How can I set the maximum current in my CircuitLab circuit?
You need to be careful here. &quot;... my power pack has a limit of 2A.&quot; What happens when you try to draw more current? Will it shut down politely or will it go on fire? Is 2 A the rated maximum (and you have to make sure you don't exceed it) or is it the value at which it will safely limit the current (and you don't have to worry)?
You have two loads:

10.5 Ω: \$ I = \frac V R = \frac {12}{10.5} = 1.2 \ \text A \$ roughly. (Batteries aren't precision devices.)
120 Ω:  \$ I = \frac V R = \frac {12}{120} = 0.1\ \text A \$
\$Total\ load = 1.2 + 0.1 = 1.3 A\$.

You're safe.


... but how come, if you open the circuit in CircuitLab and hover with your cursor over R2 or the battery, it says 10.9A, not 1.2A? Why would this be?




simulate this circuit &ndash; Schematic created using CircuitLab
Figure 1. Test circuit.

Figure 2. Simulation results.
Steps to reproduce:

Connect a 3.3 V source to drive the MOSFET.
Double click the MOSFET and change the V_TO (turn-on voltage) to 2.0 V. I didn't look up the VTO for the IRF530 so you need to check that it's suitable for 3.3 V logic.
Then check the currents. I'm getting 1.067 A which is about right as you have two resistances in series with EM1: R2 and the resistance of MOSFET.