|  | PRESSURE LIMITING DRIVER (PLD) SUMMARY |
| The Clarke PLD equipped engine is a UL/FM* certified diesel engine fire pump driver which reduces pump speed to limit the maximum pump discharge pressure to prevent over-pressurization of the sprinkler system. |
| Clarke PLD-D equipped electronic engine models can be Factory Set to limit discharge pressure at any specific pressure between 100 psi and 350 psi. (Note: This Factory Set point is not field adjustable). |
| The PLD-D senses sprinkler system water pressure via a transducer installed in a sensing line connected to the pump discharge pipe (between the pump flange and the discharge check valve), and speed changes are accomplished by the engine ECM (Electronic Control Module). |
| A PLD-D model engine requires a controller equipped with visible and audible alarms to comply with NFPA 20 (2003) Par 12.4.1.3 (8). |
| When using a Clarke PLD equipped engine, NFPA 20 (2003) requires the installation of a pressure relief valve. |
