LT-1900 Time Based Stopping
Performance Monitor Overview
The LT-1900 is a time based stopping performance monitor that utilizes a high resolution linear transducer and
controller to measure the machine stopping time in milliseconds and also the SPM of the machine. The linear
transducer is attached to the subject machine and is driven on a 1:1 linear
ratio by the machine. The stopping time of the machine will be displayed on every stop and can be easily read on
the bright red light emitting diode (LED) display on the front panel of the unit. The SPM of the machine will be
displayed during the machine cycle.
Individual LED indicators are visible and easily define the existing status of the unit during the machine cycle
(shown above). All system programming and diagnostics are front panel mounted and controlled which will minimize
downtime while enhancing operator safety and machine maintenance. All operating mode selections are supervisory
controlled by a keyed selector switch which meets all OSHA and ANSI standards for mode selection supervisory
To program the Warning Time and the Limit Time setpoints, the user inserts the programming key into the lock and
turns to the desired position (status LED illuminates). By depressing the +/- buttons to the desired time setting
and turning the key back to the Run position, the new warning/failure time setpoints are saved. All errors and time
value setpoints are permanently stored in the EEPROM memory which does not require a battery backup. The user
cannot change or reprogram the Warning or Limit setpoints while the machine is in motion, which is an additional
The dual force-guided captive contact safety output relays of the LT-1900 are always de-energized when the
programming key is not in the Run position. When the key is in the Run position, the safety output relays are
always energized as long as there are no internal or external faults detected. When a fault is detected, it is
recorded within the system in non-volatile memory along with the last stopping time. If the power to the LT-1900
Monitor System is removed and reapplied, the last error to occur will come back up and prevent any further use
until the programming key is used. Only the key turned to the reset position can clear a fault. If no fault
occurred but the programming key is moved into the reset position, the output relays will de-energize as a safety
feature. Motion detection will still be monitored while in the Reset position even if the linear transducer has
The LT-1900 system complies with OSHA code 29 CFR 1910.217 and ANSI Codes B11.3-2012 and
B11.2-2013 for monitoring and control reliability standards. The unit will automatically prevent the activation of
a successive stroke if the stopping time deteriorates beyond the brake limit setpoint. Required on any press that
has a single stroke mode and uses either a two-hand control, light curtain or type B gate system.
Non-volatile EEPROM Memory
All diagnostic faults and setpoints are permanently saved in non-volatile memory which does not require battery
backup. Information is retained indefinitely after a power loss or machine shutdown.
The advanced circuitry and user friendly design on the LT-1900 allows both programming and status monitoring to be
performed from the front of the compact panel. There is no need to enter the control panel to adjust switches or
thumbwheels which will enhance both safety and productivity.
System Self Diagnostics
Control displays status and system fault codes are on the LED display. A detailed definition, cause, and cure
listing is supplied within each installation and operation manual.
Predictive Maintenance Diagnostic Tool
The unique "warning" feature on the LT-1900 allows for predictive maintenance to be scheduled on the machine, which
will minimize downtime. Factors which will be monitored and affect stopping time: machine cycle speed,
counter-balance air supply, tooling weight, clutch air supply, exhaust restrictions, wear
Stop Time Measurement Built-In
The built-in stop feature initiates a stop signal in the downstroke. This is required information when calculating
the location of point of operation guarding systems or palm button assemblies.
Complete Package Supplied
Everything you need to install and operate the LT-1900 is supplied.
• LT-1900 Controller
• Linear Transducer and Brackets
• 40' (12m) of transducer cable
• Dimensional and technical data
• Installation and operation manual