This happens when the overload is tripped on the reversing line starter. Reset the line starter by pressing the button or tab by the overload devise in the electrical box.
The machine has an analog scale called a vee scope. This scale is a black vee sloping down from right to left. When the machine is operating there will be two vee's that meet on the scale and the amplitude can be read at the bottom of the scale at the point the two vees meet.
The Complementary Weight (CW) will be printed inside the front cover of the machines instruction manual.
The machine has an eccentric shaft that causes the machine to oscillate when it is spun at 30 HZ. The shaft is threaded and can be adjusted by loosening the locking screw and adjusting the shaft in or out to decrease or increase the dynamic force. The end of the shaft can be aligned with a scale on the machine to determine the actual load on the machine. The MACHINE MUST BE OFF BEFORE ATTEMPTING TO ADJUST THE ECCENTRIC.
On the Automatic machines there is a Static Force Controller that is used to load the specimen in the machine. Check the manual and the verification sheet, then adjust digital potentiometer to the force required on the test specimen. The SFC will load the specimen and maintain the load during the dynamic testing.

Instron software verification documentation, accreditations and certificates can be viewed and downloaded here

It is the customer's responsibility to arrange for the off-loading, unpacking and transportation of the equipment to the test site. This includes all insurance and safety responsibilities. If installation is included with your system, please allow the Service Engineer to open boxes and verify all parts and contents. This helps to avoid the possibility of losing small pieces or parts.
The motor has an overload protection devise on the 3 phase line starter in the electrical box. Turn off the main power and open the box. At the bottom of the reversing line starter is a reset button, it must be pushed in to reset the devise. At least three different styles of line starters have been used over the years, but all of them have the overload in about the same place.
There are several things to consider here: 1. The controller type 2. The software 3. Power to the pump Check in the following order: 1. Make sure the Control box is on and the machine software is running in a pretest menu. 2. Make sure there is power to the electrical box. 3. Make sure the machine limit switch is not tripped or stuck in the tripped position. 4. Make sure the stop button is reset to the on state (Many machines have a twist to unlock switch). 5. Make sure the machine is not showing an overloaded condition on the input load signal.
This can be a difficult and serious problem to solve. Call 1-800-473-7838 for Technical Support.
  1. Inspect the three valves that control the loading, they are the micro valves - load and unload knobs that are turn to make an adjustment and the fast advance lever valve. The lever should point in the neutral / off position half way between the load and unload settings. The unload micro valve should be in the closed position fully CW. The load valve will need to be turned CCW to open it and move the hydraulic ram or test a specimen. 
  2. If the valves are correct and there is still no load applied, check the oil level in the reservoir.
  3. Next check the cylinder and piston assembly to see if it is leaking oil (defective seal). Generally the protective boot on the ram will need lowered to inspect this area.
If the indicator works after rebooting then it is an intermittent problem. Check the power supplies and connections to the MK III. Also try to press down on the chips on the CPU board it is the centerboard in the indicator.
Check to see the string cable from the position devise is attached to the ram assembly. Check the encoder cable connection on both the encoder box and controller for proper installation. Replace the encoder or the encoder board in the controller.

First: The limit switch rod on many of these machines has a dual purpose; if the crosshead has been run up and is resting on the limit it will prevent the pump from coming on. Back the adjustable crosshead off until this limit is no longer tripped.

Second: There is a pica fuse on the MMR rack in the back of the control box for each relay. The fuse is to the lower left of the relay socket on the board. The fuse is a 5 amp - plug in style that looks like a resistor.

The limit switch rod on many of these machines has a dual purpose; if the crosshead has been run up and is resting on the limit it will prevent the pump from coming on. Back the adjustable crosshead off until this limit is no longer tripped.
The computer must be on, the software loaded, in an application and the load cell calibrated.
  1. Make sure one of the four load range buttons is selected on the load module. 
  2. Check to machine sure the load transducer cable is connected at both the transducer and the console. 
  3. Check the Mark III display in Mode 1 (turn off the indicator and back on). It is now in mode 1 and the load range selected should be displayed in the lower left corner of the display. When different ranges are selected on the load module the correct value should be display on the indicator. If it displays 0.0 in every range the software has lost the information. Pull you last verification certificate and call for support.
  1. Make sure the correct Range Button is pressed on the Extensometer Module - usually the Low (D) or Medium Low (C). 
  2. If present check the switch for the AC is selected. 
  3. Make sure the correct extensometer scaling number is entered in the scaling potentiometer on the extensometer module. 
  4. Make sure the standby switch is in the on position on the recorder X - axis module.
You have four options: 
  1. Purchase a System Support Agreement. This provides you with priority in the call queue, remote access to our engineering staff, discounts and additional services for one full year. 
  2. Sign-on to our Consultation Service line. This Fee based support provides you with priority in the call queue for those times that you just specific help. 
  3. Limited Free Technical Support on a call back basis. 
  4. Schedule a Field Service Engineer to visit your site.
All the SF series machines have a fixed oscillating frequency of 30 HZ that is maintained by a synchronous motor.

Most communication errors can be solved by powering down all equipment, including machine frame, control tower and computer. They should then be powered back on in the following sequence: machine frame, control tower and computer. This should result in communication being re-established. If not, check all cables and connections and perform the restart that was described above. If this does not fix your problem, then please call Instron Tech Support at 1-800-473-7838. Please make sure that you have all relevant serial and model numbers at hand when calling.

The complementary weight was set at the factory when the new machine was new to cause maximum amplitude when the machine is run. This could be considered the resonate frequency of the machine. When a specimen or fixtures are added to the osculating platen, weight equal to the specimen or fixture must be removed so the weight of the osculating platen is always the same. See the instruction manual on determining and checking that the correct amount of weight is present on the machine.