
Manual & Power Seat Universal Life Testers
The Life Tester is a very flexible control system intended for endurance testing of either mechanical devices with 12 VDC motors (requiring up to 50 amperes), or non-powered mechanical devices, using suitable fixturing and pneumatic actuators.
The basic form of this tester operates only D.C. motors and can accommodate up to four motors. This can take the form of a single 4-motor assembly (such as a six-way power seat track with a two-way power recliner), or four single-motor assemblies (such as a stand-alone seat recliner, or a power window regulator), or a combination of both. Also, not all of the four output channels need to be used. Note that suitable mechanical fixturing is necessary in
almost all test situations. The customer can either supply test fixtures, or we can provide them at very competitive prices. The top surface of the tester is ground steel (for attaching magnetic devices), and has integral mounting holes for attaching mechanical fixtures.
The upgraded version of this tester has an additional valve pack at one end that includes four double solenoid air valves with a single pressure regulator under each station and quick disconnect fittings. Each valve operates in tandem with a motor output so that all of the capabilities mentioned above can be simply applied to a pneumatic actuator on a test fixture instead of a motor. This means that the tester can accommodate up to four actuators. It
is even possible to mix motors and pneumatic actuators!
Once the mechanical test arrangement is set up, the tester is manually programmed through an operator interface to operate up to two motors (or actuators) concurrently, in any directional combination, based on any of three operation modes: current, time or limit switches. These three modes refer to what input is required to cause the tester to go to the next step in the desired sequence. In the case of "current", the tester is looking for motor stall
current (such as the end of travel) which is manually set using an integral, analog, dual set-point (center zero) current meter for each motor channel (mounted on the front panel). In the case of "time", a simple timer in the operator interface runs out causing the tester to index forward one step in its program. Finally, the "limit switch" mode allows the test to be operated between two limit switches with the tester looking only for an electrical contact closure of almost
any type or a two wire prox.
The tester can be set up to run up to twelve sequential steps. There are provisions within each step for inrush current ignore (since motors will often draw stall current upon start-up), minimum stall time (to sense a jammed mechanism), stall time (some test specifications require this feature), and motor cooling time (since any type of endurance testing usually generates excessive heat build-up).
The main screen on the operator interface includes provisions for local or remote voltage sensing (as some specifications require), which operating mode is desired (see above), total cycle time (to allow additional cooling time, or control of the intended end of the test), and cycle count and reset functions. There are also fault detecting provisions and messages displayed on the main screen as well as a test sequence status window (in case the tester is "in-cycle"
and nothing is happening at the moment).
The operator interface software in these testers includes help screens and operational instructions. Generally, because this software appears so intuitive, most operators are able to quickly program relatively complicated tests with little or no training!
The entire tester operates on 115 VAC (requiring a 15 ampere circuit), and shop air if equipped with the air valve upgrade. The tester weighs slightly over 500 pounds, and is mounted on full swivel locking casters that allow it to be rolled in any direction and through standard doorways. It has integral forklift tubes and can be transported in the back of a pick-up truck or van.
We usually maintain a stock of both new and used Life Testers for immediate delivery or customer demonstration. They are also available for short or long term rental, with a portion of the rental price applied toward eventual purchase.
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