RJ12 Splitter Hub with cable set

What the SPH-1 Does

The SPH-1 is a powered RJ12 splitter hub designed specifically for TrolMaster's environmental control ecosystem. It accepts a single RJ12 cable from the main controller and fans out to 8 individual RJ12 output jacks. Each output port can be connected to any compatible TrolMaster sensor, device module, or lighting adapter — CO2 stations, temperature/humidity sensors, light adapters for LED or HID fixtures, smoke detectors, and more.

Because it is a powered hub, the SPH-1 actively boosts signals rather than passively splitting them. This means signal integrity is maintained even as the number of connected devices grows — a critical difference from passive Y-splitters that degrade signal over longer cable runs or with many endpoints. The 12 VDC power supply is included in the kit and powers the hub directly.

Who Needs This Accessory

Any multi-zone or multi-fixture commercial grow using a TrolMaster Hydro-X, Hydro-X Plus, Hydro-X Pro, or Carbon-X controller will eventually outgrow the controller's onboard RJ12 port capacity. Once you're running more than a handful of sensors or light adapters per room, passive daisy-chaining introduces wiring clutter, potential signal loss, and troubleshooting headaches.

The SPH-1 is also specifically required when connecting certain TrolMaster modules that need supplemental 12 V power through the RJ12 line — including the MBS-Pro 4-in-1 environmental sensor. For operations running multiple rooms or multiple lighting zones from a single controller, adding one or more SPH-1 hubs keeps the installation organized and auditable. It is the standard expansion accessory for any scaled TrolMaster build.

Key Features for Commercial Installations

Single input, 8 outputs: one RJ12 cable runs from the main controller to the SPH-1, which then distributes to up to 8 downstream devices — sensors, adapters, or additional modules. The hub can be positioned centrally in the grow room so individual device cables are short and manageable rather than running long daisy-chain strings across the entire canopy.

Active signal boosting: unlike passive splitters, the powered hub regenerates the signal at the hub level. This allows for a significantly larger total device count per controller — including the ability to control an almost unlimited number of LED or HID light fixtures from a single TrolMaster controller when used in conjunction with the appropriate lighting adapters. The 12 VDC supply ships in the box; no separate power accessory purchase is required.

Important installation note: if the SPH-1 is being used solely to interconnect lighting adapters back to a single LMA adapter (excluding LMA-T and ThinkGrow light systems), the 12 VDC power supply should not be connected to the hub. Refer to TrolMaster's wiring diagrams for your specific lighting adapter configuration before powering the hub.

How It Fits a Commercial Build

In practice, most licensed commercial rooms spec at least one SPH-1 per controller — and multi-tier or high-fixture-count rooms often use two or more. Mount the hub in a central, protected location: on a wall panel, inside a controller enclosure, or on a distribution board near the main controller. Run a single 16 ft RJ12 cable (included) from the controller to the hub, then branch short dedicated runs to each sensor and module.

This topology keeps wiring organized for inspections and audits, makes it straightforward to swap or add a sensor without touching the rest of the installation, and ensures every device on the network gets a clean, powered signal. For facilities that are still in design or fit-out, factoring in the SPH-1 early allows wiring pathways to be planned around a hub-and-spoke layout rather than a continuous daisy-chain — which is materially easier to service long-term.