User manual for the Johnson Controls MRA-1 Manual Reset Actuator, a trim component for the DV-5a Automatic Water Control Valve, covering installation…
The Johnson Controls Model MRA-1 Manual Reset Actuator is designed as a trim component for the TYCO DV-5a Automatic Water Control Valve. It functions to hydraulically latch the valve in the tripped position upon activation and provides an external reset feature to allow resetting of the valve after a system shutdown, such as following a fire condition. The actuator uses a plunger and seal mechanism to control water flow and pressure within the valve's diaphragm chamber.
| Maximum Pressure | 300 psi (20,7 bar) |
|---|---|
| Assembly Body Material | Bronze |
| Cover Material | Bronze |
| Plunger/Seal Material | Bronze/EPDM |
| Spring Material | Stainless Steel |
| Reset Knob Material | Phenolic/Bronze |
| Reset Knob Size | 3-1/2" (89 mm) |
| Minimum Reset Pressure | 15 psi (1 bar) |
It is used to hydraulically latch the DV-5a Valve in the tripped position upon activation and to provide an external reset feature after the system is shut-down.
The actuator must be inspected quarterly in accordance with the provided instructions.
Check for water leakage from Port E when set, verify the actuator opens during a release device test, and verify it remains open after resetting the device.
The part number for the Model MRA-1 Manual Reset Actuator is 54-500-1-000.