Rockford Systems, LLC
46
Call: 1-800-922-7533
SSC-1500 Part Revolution Solid-State Control
SECTION 4—PROGRAMMING
BRAKE MONITOR
The SSC-1500 press control has a time-based brake monitor with programmable warning and fault setpoints. The control also includes an STM
(stop-time measurement) test. This test is used on the downstroke (usually at 90°) for establishing proper safety distance when applying two-hand
control or a light curtain as the safeguarding device. The test is also used on the upstroke (at the appropriate angle that makes the press stop at
top) to calculate the warning and fault setpoints for the brake monitor.
Every time the machine stops, the control measures the time between when the valve deenergizes and when the resolver no longer detects motion.
This is the actual stopping time of the press. The warning and fault setpoints are automatically compared to this stopping time, and will alert the
operator if the stopping time is beyond either of these setpoints.
If the stopping time is greater than only the warning setpoint, a message will be displayed for five (5) seconds on the screen, and then it will
disappear. The press will not operate during these five seconds. If the stopping time is greater than the fault setpoint, the press will become
inoperable, and a message will be displayed on the screen that will stay there until you press
ENTER
on the keypad to reset the control,
acknowledging the fault message.
Brake monitor warnings and faults can be caused by several factors. Brake deterioration is one of the main factors that will increase the press’s stopping
time. If you have a variable speed drive, running the press at higher speeds will increase the stopping time due to the increased inertia. The stopping
time may also increase if you use a heavier die, for the same reason. If you have a counterbalance system, the stopping time may increase if the air
pressure is not adjusted properly based on the upper die weight. Clogs or particles in the air line or in the valve muffler may increase stopping time. Air
pressure variance can also affect the stopping time of the press.
If you are experiencing warning or fault messages more frequently, inspect the machine and perform any necessary repairs to improve the press’s
stopping ability. For example, if your brake is deteriorating, it may need a new lining, or you may need to tighten or replace the engaging spring(s)
on it. DO NOT increase the warning and fault setpoints just to avoid nuisance stops. You will also need to run a new series of STM tests on the
downstroke to establish the new safety distance. You will then need to remount or move your light curtain or palm buttons (if they are used for
two-hand control) further away from the point of operation according to the new safety distance.
HOW TO RUN AN STM (STOP-TIME MEASUREMENT) TEST
Select the
ON
position of the program OFF/ON selector switch. One of
the MAIN PROGRAM SCREENS will be displayed.
On the MAIN PROGRAM SCREEN, use
↓
and
↑
on the keypad to scroll
through the program options. Press
ENTER
when the pound symbol (#)
is next to BRAKE MONITOR. The security code screen will be displayed.
See Figure 4.19. You will be prompted to enter the security code. See
page 52 for information on programming the security code.
Press
ESC
to stop and return to the MAIN PROGRAM SCREEN. Press
BKSP
to backspace or press
CLR
to delete the entry and start over.
Press
ENTER
when finished. After the correct security code has been
entered, the BRAKE MONITOR SCREEN will be displayed.
See Figure 4.20.
Figure 4.19
Security Code Screen
ENTER SECURITY CODE
_ CODE
Figure 4.20
Brake Monitor Screen
BM Fault Setpoint
BM Warning Setpoint
>STM Test
(Continued on next page.)
