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 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.

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.

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.