Let’s face it, the way we use power devices is changing. This is a reflection on the changing fixture counts in our rigs. We have fewer traditional incandescent fixtures, of course, and a bigger percentage of gear with solid-state LED light sources. In addition, among incandescent fixtures, the shift to lower-wattage compact filament is reducing dimming loads.
Needless to say, this has resulted in a steady erosion of the “dimmer beach” of yesteryear. Perhaps in the future it will be dubbed “dimmer sandbox.” But if the fixtures are changing, incandescent fixtures and dimming technologies are not likely to completely vanish from entertainment lighting anytime soon.
Because it’s unwise to place a device requiring constant power on a dimming circuit, however, traditional dimmers are definitely on the decline and newer relays are on the rise. Along with simplicity of a simple on/off switch, relays have the advantage of being able to be remotely controlled via a control signal.
Johnson Systems’ J-PACK brand encompasses both the company’s Hi-Performance Dimmer Pack and Hi-Power Relay Pack product ranges. Both reflect the changing needs for dimmers and relays in the world of entertainment lighting.
They share more than an external resemblance — both can be wall-mounted for permanent installations, mounted within 19-inch racks, pipe-mounted or used as portable units.
Both are also designed to be ganged together for system expansion, and both have a standby power consumption of less than one watt, enabling them to comply with the International Energy Agency’s (IEA) “One Watt Initiative.” But they also have features on the inside that set them apart.
J-PACK Hi-Performance Dimmer Pack
Available in various sizes and configurations, Johnson Systems’ range of six-channel J-PACK Dimmer series models are rated at 1,560W and can be used for prolonged
operation. Features include hydraulic magnetic circuit breakers for optimal safety and minimal false tripping risks.
The units offer an LCD user interface along with analog inputs and contact closure inputs, and the company’s on-demand MagLev thermal management keeps the units both cool and quiet. At the same time, J-Pack Dimmer Series’ “lamp warming” procedures are designed to improve lighting performance while extending lamp life.
J-PACK Hi-Power Relay Pack
Johnson Systems’ J-PACK three- and six-channel Relay Packs are rated at a full 20 amps per circuit. They are designed for dry contact and DMX power control of LED fixtures, and work well also with distributed commercial fluorescent lighting installations.
The J-PACK Relay Pack offering includes 120V, 208V, 240V and 277V options. For installation applications, the ability to communicate to multiple devices long distance via DMX512 protocol can keep electrical installation cost in check while allowing for centralized control.
Johnson Systems also notes that all circuits within its J-PACK Relay Packs contain fully isolated output power relays rated to 50 amps. The company adds that self-contained units with UL489-rated hydraulic magnetic circuit breakers optimize safety while eliminating the need for separate branch circuit breakers and relay panels.
Johnson Systems J-PACK Series Features
Features Common to Both:
• LCD user interface for setup/monitoring
• Keypad lockout preventsunauthorized access
• Over-heat and over-currentprotection
• Available in various voltages, outputand mounting configurations.
• Standby power consumption of lessthan 1 watt
• ETL Listed, compliance with UL508and CSA 22.2.
• Up to 10-year product warrantyavailable.
• Size: 18” x 7.5” x 3”
• Mounting Options: Wall, Pipe,Rack, Rubber Feet
• DMX512 start-addressable in singlechannel (offset) or individually (patch)
Dimmer Pack Features:
• Dim standard or low-voltage incandescent quartz lamps. Compatible with SCR dimmable LED lamps and fixtures.
• Individual dimmer profile selection permits safe and silent control of non-dim lighting loads.
• DMX “snapshots” with scene playback.
• “Lamp warming” feature extends lamp life
MSRP: Starting at $1,875
Relay Pack Features:
• Power control via dry contact or DMX512 lighting control protocol
• Designed for LED fixture power switching
• Heavy-duty “air gap” output relays rated to 50 amps
• Programmable DMX Status Hold timeout
• Dual auxiliary contact inputs permit power management interface with BMS, photocells, occupancy sensors, HVAC, security and audio HVAC, security and audio
MSRP: Starting at $1,375
