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Common faults: I. Abnormal liquid suction by the metering pump. Rotate to the 100% stroke length position. This allows the entire assembly to rotate so that the leakage outlet on the backplate aligns with the lowest point of the pump. Adjust the hydraulic end and diaphragm to the appropriate positions during pump operation. For reaction time, the pulse duration may not be long enough. Relative to the standard pulse width of 80 msec, the flow monitor pulse width extension can be activated to increase the pulse width to 300 msec. Activate the smart transfer switch, remove the cover fixing the circuit board, and take away the jumper X-1. This activates the extended function, allowing more time before a fault is indicated. The metering pump is equipped with a self-venting pump head, enabling self-priming liquid suction. Keep the suction line as short as possible. II. Replacing the diaphragm of a metering pump: Trouble often arises when removing the old diaphragm. Some additional advice on how to remove the old diaphragm is provided. ⒈ After the pump head becomes loose, but before removing it, adjust the stroke length to 10% position. It ensures that the electromagnetic shaft has sufficient pressure to maintain a secure connection, thereby allowing the diaphragm to be removed. ⒉ Pull the hydraulic end outward to disengage the screw from the socket. Grab the liquid end and rotate counterclockwise. With a little resistance, the diaphragm can be unscrewed. ⒊ The measured chemical substances may crystallize at the hydraulic end, preventing the check valve ball and seat from functioning properly. ⒋ There may be a gas leak at the suction side of the metering pump. The suction side connector on the hydraulic end may be missing an O-ring or the suction valve connection may be loose. III. When using flow monitoring to measure a high-viscosity medium, a flow error signal is received during the liquid introduction process; what can be done to resolve this issue? This can be achieved by loosening the screws on the 4 pump heads in order to move the hydraulic end. Reduce the rotation stroke length to 10% and grasp the hydraulic end, then slide it out of the screw hole; the screws will not be in contact with it, but they will still hold the backplate and diaphragm in place. Then rotate this component counterclockwise; with a slight amount of resistance, the diaphragm will loosen from the electromagnetic shaft. If the diaphragm is not yet loose, apply some lubricant to the contact surface between the diaphragm and the electromagnetic shaft. After placing it for a few minutes, gently tap the diaphragm with a small plastic hammer. Then proceed again as described above. IV. How to prevent the stroke positioning motor of the metering pump from burning out? 1. Remove the 4 screws that hold the pump head in place. The screw is located on the back of the metering pump. ⒉ Check whether the discharge pipe is installed and whether the discharge valve is closed. During the priming phase of the metering pump, the discharge valve needs to be open. Note: Not all metering pumps have a drain valve. ⒊ After the diaphragm has been installed and the leak drainage holes on the backplate are in a vertical position, install the pump head. Ensure that the suction valve is aligned with the liquid leakage outlet, and that the screws on the hydraulic side are aligned with the corresponding 4 holes. V. Is the flow rate of the hydraulic metering pump reduced or inaccurate? 1. Unscrew the vent valve among the three valves. ⒉Fully replenish oil through the oil refill valve.