- Hydraulic pump control is a very common method of overfill protection that can be controlled by the Pump/Aux Relay 2.
- It is best to use a high quality solenoid controlled Normally Open valve appropriate for the application. They are available from many hydraulics component vendors.
- The solenoid can be wired directly to the FINCH II pump relay. This relay will shut off the pump when the liquid level reaches the HH (High High) alarm point set in the TD100 programming.
- The pump can be reactivated to clear the hoses of product. The next shutdown point will be the SPILL alarm level also set in the TD100.
Important:
Unlike the HH alarm the SPILL alarm disengages the pump and cannot be acknowledged, therefore the product will need to be pumped down externally by at least 1” below the SPILL alarm level before the onboard pump will re-engage.
- The Parker valve is installed between the hydraulic pressure line (on the input of the controls manifold) and the by-pass line to the reservoir.
- A "T" fitting is installed on each line and the valve is installed in between these fittings.
- The Normally Open valve is supplied power when the system is good to pump forcing pressure through the control body.
- The system removes power in an alarm event allowing the pressure to bypass the controls.
