COOPER INDUSTRIES INC FH1847N Manual De Usuario
T245 Control System Manual
22
Output
Param
Value
1_
2_
3_
4_
5_
6_
+
-
Threshold
Start PWM
Max PWM
Ramp Up
Ramp Down
MAX
MIN
Store
Key
Figure 7 R1300+ Set-Up Panel
The Ramp parameters control how fast the output builds up or down to the final
value according to a first-order difference equation. The separate Ramp Up and
Ramp Down time constants allow you to tune the valve response for smooth, non-jerky
actuation. The Threshold, Start PWM, and Max PWM parameters control the transfer-
function from input (joystick position) to PWM-output value, as shown in Figure 8. The
joystick position can go from 0 to 127. The threshold is simply the deadband beyond
which the joystick must move in order to actuate the PWM output. The PWM output
starts at Start PWM as soon as the joystick has exceeded the threshold, and maps linearly
with joystick position up to Max PWM.
Ramp Down time constants allow you to tune the valve response for smooth, non-jerky
actuation. The Threshold, Start PWM, and Max PWM parameters control the transfer-
function from input (joystick position) to PWM-output value, as shown in Figure 8. The
joystick position can go from 0 to 127. The threshold is simply the deadband beyond
which the joystick must move in order to actuate the PWM output. The PWM output
starts at Start PWM as soon as the joystick has exceeded the threshold, and maps linearly
with joystick position up to Max PWM.
0
0
Threshold
127
Max PWM
Start PWM
PWM Output
Joystick Posit
Figure 8 Proportional (PWM) Output Function