GENERAL INFORMATION The SMMC-3 Control Panel manages snow and ice melting equipment for sidewalks, driveways, gutters, downspouts, etc. Suitable for controlling all types of heating cable systems, the SMMC-3 can monitor snow and ice accumulation in three separate zones. The SMMC-3 programming allows each zone to be controlled independently or on a priority mode basis.
Installation & Operating Instructions Fig.2 Sample Application Illustration power contactors(s) SMMC-3 snow/ice sensor options power contactors(s) maximum 2 sensors per zone power contactors(s) 120 VAC, to contactor coils * maximum 1 SMPS-1 sensor per zone 12 0 VAC, 450 VA WARNINGS A qualified electrician must install the SMMC-3.
The SMMC-3 terminal blocks serve 5 distinct connection sectors (see Fig 4), they are: SMTS-1 temperature sensor. SMAS-1 aerial sensors / SMGS-1 gutter sensors (one each per zone). SMPS-1 in-ground sensors (one each per zone). Output to power contactors (one each per zone). Control power input.
Fig. 4 SMMC-3 Control Panel (Typical Connections) SMMC-3 Power SMTS-1 SMAS-1/SMGS-1 SMPS-1 Contactor Output Input Heater Power Supply SMAS-1 or SMGS-1 Control Sensor W ire W iring Contactor/ Connection Box To Heater Cables SYSTEM CHECK To cycle system and check sensor operation: Before you energize the controller, confirm: ·...
OPERATION The SMMC-3 is a programmable controller, capable of controlling three separate snow/ice melting zones. A control relay for each zone is included in the SMMC-3 to operate a contactor for each zone to energize the snow/ice melting equipment. There are two operating mode selections possible with the SMMC-3: MODE 1 INDEPENDENT In this mode each snow/ice melting zone is controlled independently.
ZONE ASSIGNMENT To de-energize the manually activated heating The SMMC-3 uses the concept of a zone system to most equipment, use the toggle switch on the front panel. efficiently control snow/ice melting equipment. The term zone means an area (either surface area or roof/gutter When operating in Mode 2 Priority, the manual area, or some combination of both) heated by a specific...
PROGRAMMING INSTRUCTIONS 2.Mode: 1 or 2 <No.1 > <No.2 > The SMMC-3 program has been structured into 6 levels; within Pressing UP selects Mode 1 (Independent). each of these levels are further degrees of selection. Each Pressing DOWN selects Mode 2 (Priority). programming step is clearly described on the LCD, and easily After pressing the UP button for Mode 1, the program adjusted by the UP , DOWN , and SET buttons.
Pressing UP activates the selected sensor. Press the SET button to adjust the relay hold time for the Pressing DOWN de-activates the selected sensor. snow melting zones. The relay hold time is the amount of time After pressing the UP or DOWN button for <P.Zone3>, the the snow melting zone remains energized after the moisture sensor is dry.
Error Messages The error screen will flash intermittently with the standard The SMMC-3 will display an error message whenever a problem is operating screen. To cancel the error message press the detected with the connection to the SMTS-1 or any of the SMPS- DOWN button when the error screen is showing.
TROUBLESHOOTING GUIDE SYMPT OMS PROBABLE CAUSE CORRECTION System is not operating and system No Power to SMMC-3 Turn on power using switch on front light is not lit. panel. Display is not lit and power switch Supply not energized or power Check power supply.
SMMC-3 CONTROL PANEL (ACCESS COVER REMOVED) SMTS-1 Zone 1 Sensor Zone 1 Output Input SMPS-1 Terminal Block (must be programmed Connector to Zone 1 Sensor To activate) Contactor Coil Input SMAS-1 or (Default) SMGS-1 (Default) Zone 2 Sensor Zone 2 Input Zone 2 Input SMAS-1 or for SMPS-1...
SPECIFICATIONS Electrical Mechanical Certification Power Requirements NEMA 12 non-metallic enclosure 120 VAC, 50/60 hz, 480VA System Memory Control Relays Outputs Environmental Specifications Non-Volatile: no data loss 120 VAC, Pilot Duty, 120VA Ambient Operating Temperature Range with a loss of system power Power Supply Sensors -4°F to 160°F / -20°C to 70°C...
LIMITED WARRANTY AND LIABILITY Nelson warrants that if there are any defects in material or workmanship in any heating cable or accessory during the first year (two years on MI or self regulating heaters) after the date of its purchase, we will provide new products to replace any defective items, or we will refund the purchase price paid for the accessory or cable, not including any labor or other installation costs.