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Weathermatic SMARTLINE 12 Station Indoor/Outdoor Controller | SL4800

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Free Shipping on Orders over $149
Sale Price $424.98
Our Price $689.89
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12-zone base model controller expandable to 48 zones.

Features & Benefits of the SL4800 Controller

  • 12-zone base model, expandable to 48 zones using SLM12 12-zone hot-swappable modules (Indoor/Outdoor rated)
  • Internal transformer with commercial terminal block, On/Off power switch and LED status indicator
  • Large backlit LCD display
  • 2 run modes: Standard mode runs user input zone run times; Auto Adjust mode requires SLW Series On-Site Weather Station to calculate weather based run times that override user input zone run times
  • Rain/Freeze sensor bypass/active button located on face panel displays sensor status with tri-color LEDs (red indicates sensor is prohibiting irrigation; orange indicates an extended rain delay after weather station rain sensor permits irrigation; green indicates normal operation)
  • 4 programs: A, B, C; program D can operate concurrently
  • 8 start times per program
  • Nonvolatile memory and real time clock/calendar circuit to retain programs as well as correct date and time - with no battery required
  • Zone run times settable from 1 min. to 9 hrs. 55 min. with operation countdown displayed in hours, minutes, and seconds (zone run times overridden by weather based calculated values in Auto Adjust mode)
  • Watering day selections of custom days of the week, odd/even, or interval days
  • Omit settings: omit time of day window, omit day(s) of week, and omit up to 7 calendar dates
  • Monthly % adjust by program, for simple year round water budgeting


  • Input: 120VAC/60Hz @ 400mA for 5 valves
  • Output: 28VAC, 1.2A maximum
  • Fuse: 1.5A, slow blow
  • Dimensions: 15" W x 16-1/2" H x 5-7/16" D (38,1 cm x 41,9 cm x 13,8 cm)

Auto Adjust Features

  • ZIP Code input (5 digit) or Latitude input (+/-60 degrees from EQUATOR) establish location of site for solar radiation calculation
  • Sprinkler type input allows selection for zone sprinkler type (SPRAY, ROTOR, DRIP, BUBBLER) with preset precipitation rate or specific input of the zone precipitation rate (.2 - 3.0" per hour)
  • Plant type input allows selection for zone plant type (COOL TURF, WARM TURF, SHRUBS, ANNUALS, TREES, NATIVE) with preset crop factors or specific input of the zone crop factor (10 - 300%)
  • Soil type input allows selection for the soil type (CLAY, SAND, LOAM) and slope (0 - 25 degrees) for the purpose of automatically calculating a run/soak period to virtually eliminate run off
  • More/Less is settable by zone (-50% to +25%) for the purpose of fine tuning Auto Adjust run times to accommodate factors like shade, wind, and sprinkler inefficiencies

Not Available
Not Available

Advanced Functions

  • Fault review displays all faults, including open and shorted zones
  • Diagnostic test function using on-board multi-meter displays transformer voltage; milliamp measurement for each zone
  • Built-in valve locator function for locating hidden valves by simply listening for the audible chatter of the solenoid created by a unique electrical frequency (patent pending)
  • Review menu displays accumulated ET deficits by zone (in inches) and corresponding zone run times for the next available watering day
  • Review menu displays maximum run time and minimum soak time used during Auto Adjust mode
  • Review menu displays temperature readings (daily high/low) for previous 5 days
  • Review menu accumulates total run times by zone from the last reset date
  • Rain delay of 1 - 7 days may be selected (to pause and automatically resume operation)
  • SLW Weather Station extended rain delay programmable from 0 - 99 hours
  • Run/Soak cycles allow setting of maximum run time and minimum soak time by program for use in Standard mode only
  • Zone-to-zone delay programmable for 1 min. - 3 hrs. to accommodate slow closing valves and recharging of water supply
  • Master valve timing sequence with zone-valve programmable by "On Delay" (1 sec. - 1 min.; 2 sec. default) and "Off Delay" (1 sec. - 3 min.; 5 sec. default) to allow for line fill and slow-closing valves
  • Master valve/pump start operation assignable On/Off by zone
  • Clear program function to selectively delete an individual program
  • Clear all function to delete all programs
  • Backtrack stored program feature allows contractor to easily store a default program and retrieve the saved program in the event a customer improperly reprograms the SL800
Product Type:
Controller (AC)
Enclosure Type:
Max Station Run Time (HRS):
Light Commercial, Residential
Enclosure Type:
SmartLine 4800
Freeze Sensor Compatible:
Power Source:
AC Powered
Number of Programs:
Start Times Per Program:
Sensor Compatible:
Rain, Freeze
Rain Sensor Compatible:
Controller (AC)
Residential and Light Commercial
Enclosure Type:
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Browse 11 questions Browse 11 questions and 16 answers
My system pumps out of a body of water. Is this the timer I need to buy?
A shopper on Jun 4, 2014
BEST ANSWER: Yes, the SL4800 has a Master Valve / Pump Start Relay port so that it can water using metered water, pump station, etc.
Is this timer compatible with a Munro MPLC24T Smart Box pump start relay?
A shopper on Oct 23, 2016
BEST ANSWER: Yes, need to get box with 24 volt relay coil to call for water on master valve circuit of sprinkler controller.
This timer will control 8 valves. I need an outside timer and want it electronic. What is my best choice?
Terry H on Jan 13, 2015
BEST ANSWER: The Sl1600 expanded to 8 zones has all of the same features and is less expensive.
sl4800 110 hook up?
A shopper on Mar 19, 2014
BEST ANSWER: Yep; no special wiring needed. Just plug into existing outlet.
I have multiple valve manifolds each with master shutoff valves. Does the Weathermatic SL4800 supply enough power and have assignable channels for multiple master valves?
Does the Smartline 4800 have PC software to allow Ethernet hook-up and control?
A shopper on Mar 18, 2016
BEST ANSWER: The SL4800 has a 2 amp rated transformer, enough to run 3-4 valves at a time.

In order to have internet access to the controller, you will need to add the SL-AIRCARD. It is cellular cloud based which does not require Ethernet or PC software.

You can manage everything from any internet enabled device.
Weathermatic SL AirCard | SL-AIRCARD1-ATT
Weathermatic SL AirCard | SL-AIRCARD1-ATT
Will the controller be able to control a 24 V system master valve and incorporate flow sensor information?
Joe D on Oct 28, 2016
I have an MVP Short message saying keep clear. what is this referencing toward. A pump in the Box at a different location?
Joshua on Apr 16, 2016
when turning dial to manual an scrolling to some stations it says used ? I need access to control times for zones same with turning to station times its a weathermatic smartline that's all I know
brad c on May 21, 2015
I need 36 zones in a timer. What would be the timer and any add on to get?
Greg G on Mar 26, 2012