There are 2 types of Photocells that may be used with the iDIM/iDH panels.
The PCELL 3WI TZ three wire indoor ten to zero photocell, it connects directly to the photocell/analog input of the iDIM/iDH panel. It requires 3-#18ga wires and should not be installed more than 150ft from the Micro panel. Longer distances require the use of shielded wire. A shielded pair may be used with the shield acting as the Ground conductor.
The PCELL 2WO or 2WI are 2 wire photocells sensors that connect to a Photocell Control Card by 2-#18ga twisted pair wires. The photocell may be mounted up to 200ft from the card. A PCC-1 or a PCC-3 photo cell control card may be used.
Acuity offers two styles of photocell inputs cards that may sit on the GR2400 bus and send levels over the bus.
The PCC-1 (Photocell Control Card with one Input) takes either 2 wire photo cells. The photo cells may not be enabled/disabled through programing but can be with contact closure, in most cases the PCC-1 will not be used for indoor light harvesting.
The PCC-3 cards accepts three photocells which may be enabled or disabled over the bus. For non-dimming relay panels the PCC1 or 3 act like light level controlled switches and may turn ON and OFF relays at specific numbers which equate roughly with foot-candles.
A PCC-1 will only accept 1 photo cell and may only be disabled with a hard-wired contact closer.
When these cards are used with an iDH or iDIM panel, just the readings of the photocell are reported and the programming within the scene uses the data to control the loads.