Electro Cam Plus PS-6144 Series, Programming & Installation Manual

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4-4 Speed Compensation
Standard Speed Comp (cont’d)
Figure 24—Example for Calculating Speed Compensation
RPM Glue On Glue Off Difference
1st Line Speed: 200 73° 156° 83°
2nd Line Speed: 680
49° 132° 83°
Difference in Position: 73 ° - 49° = 24°
Difference in Speed:
680 RPM - 200 RPM = 480 RPM
Speed Compensation Value: Divide difference in position by difference in speed:
24°/480 RPM = 0.05° per 1 RPM
Since a shaft at 1 RPM rotates 0.006°/msec (see page 4-2), this shaft would require
(0.05/0.006), or 8.3 msec to rotate 0.05°. The speed compensation value is 8.3.
Leading Trailing Speed Comp
Leading/Trailing In the previous example, the response time of the glue gun was the same whether turning
on or turning off. While this applies to many systems, some devices have different on/
off response times. For these devices, PS-6144 controllers with the “-L” option (Leading/
Trailing Edge) provide the ability to program different speed compensation values for
the leading and trailing edges of the pulse driving the device.
Setting If the ON and OFF response times are known, jog the line to determine
Leading/Trailing ON and OFF setpoints at zero speed. Then enter the speed compensa-
Speed Comp tion values through SPEED COMP programming as described in Section 3. When
programming SPEED COMP, enter the leading edge, or ON response time at the “LE”
prompt, and the trailing edge, or OFF response time at the “TE” prompt.
When setting speed compensation on a system where zero speed setpoints have
been established, always adjust the speed compensation value. Do not adjust the
individual output setpoints!
Response Times
If the response times are unknown, jog the line to determine ON and
Unknown
OFF setpoints at zero speed. Estimate both ON and OFF response times and enter
them through the SPEED COMP function. The leading edge, or “LE” value will control
the ON timing, while the trailing edge, or “TE” value will control the OFF timing. Start
the line, run product through it at a fixed speed, and adjust each
speed compensation
value as required for proper gluing. This can be done while the line is in motion. Once
programmed, vary the line speed to confirm proper operation at all speeds, and fine
tune the SPEED COMP values if necessary.
Can’t Be Jogged? If it is impossible to jog the line, run the line at a fixed speed and set the ON and OFF
setpoints as required with SPEED COMP set to zero for both the leading and trailing
edges. Write down the ON and OFF setpoints.
Next, increase the line speed and adjust the setpoints to restore proper gluing. You
might be tempted to adjust speed comp values to do this. However, since the setpoints
were adjusted at the first speed with zero compensation, any change in compensation
value now will upset the first pair of setpoints.
Since the new speed compensation value will affect the ON and OFF setpoints already
programmed, you will need to start the line one more time and, at a constant speed,
adjust the
ON and OFF setpoints for proper gluing. Once set, vary the line speed to
confirm that the speed compensation value is accurately adjusting the setpoints over
the operating speed range.