I plan to upgrade my existing pool 'automation' system by replacing two existing Intermatic T104 240V mechanical timers that now control ON/OFF events for two Pentair WhisperFlo WP-4 single-speed 240V pumps (filter & floor cleaner) with two new Intermatic P1353ME digital timers. My desire in this upgrade/installation scheme is to control multiple daily ON/OFF events for the two WP-4 pumps - plus a third Pentair 240V booster pump that feeds a water feature - with ONE of the P1353ME timers. The second P1353ME timer will control an Aqua-Cal 240V heater, 120V/400W pool light and 24V landscape lighting (via a switched transformer). I will install Intermatic 178PA28A freeze protector sensors to both timers and an Intermatic PA122 water temp sensor. I will also install the Intermatic PE650/PE950 I-Wave wireless remote control system to control all of the various functions remotely.
The two existing T104 mechanical timers are wired with dedicated Line/Load conductors (2 each) to supply 240V to the two pumps (filter & floor cleaner). The third water feature pump is fed 240V via a double-pole breaker with the water feature pump ON/OFF functions controlled by a (failed) AquaDyne 240V X-10 controller mounted and wired into the load/control center. The failed AquaDyne X-10 controller is the primary cause & motivation for the new Intermatic 'automation' upgrade\installation.
After MUCH time spent studying the Intermatic P1353ME installation manual and the Intermatic-recommended wiring diagrams for the seven different P1353ME programming modes, I am still puzzled/confused by the wiring needed for the dual P1353ME timers in the contemplated and described installation.
The only way I see to wire ONE P1353ME to the THREE 240V pumps is to jumper the 240V Line from terminal #1 to Terminal #3,5,7 and run the Load from Terminal #4,6,8 to each pump. IINM this wiring approach will switch just ONE leg of the 240V circuit running to the three pumps leaving all three pumps 'hot' with 120V on one pole when switched 'off' at the timer. All three pump circuits are all protected by double-pole circuit breakers in the load/control center and the pump wiring runs from the load/control center to the three pumps in water-tight flexible conduit.
My major question/concern with this wiring approach is will switching just ONE leg of EACH 240V pump circuit create safety hazard in the occasionally-wet environment of the equipment corral?
Does this wiring approach violate code or typical convention?
Can anyone recommend a better/safer wiring approach to accomplish my goal of wiring all THREE 240V pumps to ONE P1353ME timer?
For reference, tomorrow I will snap and attach to this thread a pic of the existing T104 installation and the existing wiring in the load/control center.
Appreciate any and all help/guidance from the sage TFP wizards!!