A direct acting proportional only controller has a gain setting of 4 and a base point of 9 psi. What is the output under the following conditions:

a. Set level equals measured level; b. Measured level increases1 psi from (a); c. Measured level decreases 2 psi from (a).

v = P(c-r)+v0

Where : v controller output pressure in psi; initial or base point controller output pressure in psi; P controller gain (positive for direct action, negative for reverse action); c transmitter output in psi; r setpoint transmitter output in psi (3 psi when set level = 0; 15psi when set level = 100)