Mark-10 ESM303 - Preload; Load Holding; Function; Preload Value (PRELD %FS)

Models ESM303 & ESM303H Test Stands User’s Guide
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4.6 Preload
4.6.1 Function
This setting corresponds to the test stand’s response to an initial load, referred to as a preload. The
crosshead can stop and/or zero the travel display when the preload has been reached. This function is
useful for applications such as spring testing, elongation testing, and tensile and compression testing of
various materials. In effect, it establishes a reference point. It is also sometimes referred to as a touch.
Note:
Before the start of a preload sequence, the crosshead must be positioned at either physical limit switch.
Default setting: OFF
Available settings: STOP, STOP/ZERO, ZERO/GO, OFF
Label
Description
+ or –
Cycles through the available settings listed below:
STOP
Crosshead stops when preload has been reached
STOP, ZERO
Crosshead stops when preload has been reached, then zeroes the travel display
ZERO, GO
Travel display is zeroed when preload has been reached, crosshead does not stop
ENTR
Returns to the Test Function Setup menu
ESC
Exits the function without saving changes
4.6.2 Preload Value (PRELD %FS)
This setting corresponds to a preload value, defined as a percentage of the instrument’s full scale in lbF
units. The test stand’s response, as described in the previous section, occurs when this value has been
reached.
Note:
In low force applications, consider test stand vibration and crosshead acceleration, as they can be
significant enough to produce a force exceeding the preload value.
Default setting: 1%
Available settings: 0 – 100%
Label
Description
+ or –
Increases or decreases the value, in increments of .1
ENTR
Returns to the Test Function Setup menu
ESC
Exits the function without saving changes
4.7 Load holding
This setting directs the test stand to dynamically adjust the crosshead position to maintain a programmed
force. The force is programmed as a set point in a Series 5 or 7 instrument (refer to the user’s guide for
details). If the CYCLING option has been installed, load holding will be active for the period of time as
defined in dwell settings. If CYCLING has not been installed, load holding will continue indefinitely.
Pressing STOP will end load holding.
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