Product Description
4-zone base model, expandable to 16 zones using SLM4 4-zone hot-swappable modules (Indoor/Outdoor rated)
Internal 120VAC/230VAC transformer with plug and play pre-installed 6' line cord (removable for conduit-wired installations)
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
Rain/Freeze sensor bypass/active button displays sensor status with tricolor LEDs (red indicates sensor is prohibiting irrigation; orange indicates an extended rain delay; 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 to retain programs and current date and time no battery required
Zone run times from 1 min. to 9 hrs. 55 min. with operation countdown displayed in hours, minutes, and seconds
Watering day selections of custom days of the week, odd/even, or interval days (1 - 30 days)
Omit settings: omit time of day window, omit day(s) of week, and omit up to 7 calendar dates
Seasonal % adjust by program, by month for simple year round water budgeting (monthly percentages overridden in Auto Adjust mode)

ELECTRICAL
Input: 120VAC/60Hz @ 400mA for 3 valves
Output: 28VAC, 1.0A maximum
Fuse: 1.0A, slow blow

DIMENSIONS
9-1/8" W x 10-1/2" H x 4" D (23.2 cm x 25.7 cm x 10.2 cm)

ADDITIONAL MODULES: SLM4 4-zone module for use in the SL1600

Irrigation Controller Basics!
No matter what you call it, and some folks call it some pretty bad things, the clock, timer or irrigation controller is the brain or heart of your system. With any clock, there are a few key features to learn for easy, stress-free operation.
The Program is a set of instructions that tell the clock exactly when and how long to run each sprinkler valve. A multi-program clock allows you to schedule different days and times to fit the watering requirements of different kinds of plants.
Start times allow you to operate the system at any time of day you select. Many timers have multiple start times. Run times determine how long each sprinkler valve operates.
Water days tell the clock which days of the week your system should operate. If the clock has a 7-day schedule, it will display days 1 through 7. Day 1 indicates Sunday, 2 for Monday, etc.
Skip days allows you to water at odd intervals during the week. Clocks with skip day capability can have up to 30 days between watering cycles which is great for cactus or during the winter season.
Water budget allows you to automatically conserve water without reprogramming the clock. Just change the percentage display to adjust for hot, cold or rainy weather. Our clocks are grouped by manufacturer. Complete operating instructions are included with each clock/timer. Repair/replacement parts are listed with the corresponding clock.

How To Use Tips
Don't be intimidated by your irrigation clock/timer. Familiarize yourself with all aspects of operation and keep instructions near your clock. Many clocks have quick, point-by-point instructions inside the front cover. After the clock has been installed, experiment with the features and be sure you understand how everything works. If you hire someone to install your system, have him/her explain everything about your clock before you make final payment. Learn the water requirements of your plants and lawn. It will make things easier on them and easier on your pocketbook! If your clock has a battery backup, keep a spare battery handy for replacement. Fresh batteries will save your clock programs in case of sudden power failures. It's also a good idea to keep some extra fuses on hand as well. Run your system; don't let it run you.