Underhill ICC 2Wire Decoder Module
Bidding Specifications

Application 
The following bidding specifications are for the Underhill ICC 2Wire Decoder Module that is compatible with the Hunter ICC plastic wall mount irrigation controller.  When installed in any one of the four open station-module “slots”, it will allow this controller to manage up to 48 stations.   

The 2Wire Decoder Module p/n TW-ICC-48 will allow a Hunter ICC plastic wall mount controller to operate all stations exclusively on 2Wire or a combination of both multi-wire and 2Wire depending on the customer needs.  

All of the Hunter ICC controller’s programming functions inclusive of hand-held remote operation, rain sensor operation and/or master valve/pump start functions are maintained. 

Material 
The ICC Decoder Module is a 2-part clamshell plastic molded case design of Cycolac® black plastic.  The case is permanently sealed and is not field serviceable.  The approximate outer dimensions of the molded plastic module is 4” l x 2-3/8” w x 1-1/2” d (101.6 l x 60.33 w x 38.1d mm)

Inside of the molded case is a printed circuit board (PCB) containing circuitry, software and components to transmit the controller’s programming functions down a 2Wire path.  The PCB supports the following components:
•	9 (qty) vertically oriented, gold-plated pins located on the underside of the molded case.  
•	1 (qty) black and red spring-loaded connector for the purpose of programming or testing a decoder.  
•	2 (qty) colored LED’s.  One is green that will illuminate when the module is first powered “On” or when a station is operated from a programmed start or manual operation.  One red LED to indicate any one of several field fault conditions.
•	1 (qty) black “reset” button used to clear a fault condition.  

Each module has a printed label with date code signifying the quarter of the year designated by A, B, C or D and a 2-digit value for the year of manufacture. 

Electrical 
•	Maximum AC input voltage	32V AC
•	Maximum continuous 2Wire main cable current	1.0 Amp AC
•	Maximum Number of Stations	48
•	Maximum continuous solenoid current	0.6 Amp, (600mA)

Reference Underhill 2Wire sizing chart;
http://underhill.us/library/downloads/viewdownload/132-design-criteria/1059-wire-sizing-chart
Installation 
The ICC 2Wire Decoder Module has the same mechanical dimensions as a Hunter ICC 8-station station module.  The ICC Decoder Module comes with a short cable assembly with a soldered eyelet connector.  This eyelet is to be secured to a fastener located underneath the molded plastic part that holds the station modules in place.  

The installation of the ICC Decoder Module is to be performed with the 120-volt power and 9-volt back-up battery removed from the Hunter ICC controller.  Failure to follow the installation instructions may result in permanent damage to the module and will not be covered under the manufacturer’s warranty.  

Installation instructions of how to field install the module are shipped with every ICC Decoder Module and it takes approximately 5-10 minutes to complete this installation with a #3 Philips head screwdriver.  

The ICC Decoder Module is to be grounded to a ground rod, ground plate or cold-water ground depending on the installation.  Connect a #14 gauge solid copper wire between the ground terminal on the ICC Decoder Module and an appropriate grounding device.  This is only grounding requirement for this 2Wire product but must completed to satisfy the manufacturer’s warranty. 

Two solid core conductors, commonly different colors are to be connected to the L1/L2 terminals labeled on the ICC 2Wire Decoder.  The size of the conductor is based on the number f valves operated at one time and overall length of the 2Wire path. This is a non-polarized connection so there are no requirements for matching a specific color to a specific terminal.  

The 2Wire path is energized only when a station is operated from a scheduled start time or from a manual operation.  AC voltage cannot be measured across the L1/L2 terminals without either one of the program functions listed above. 

When operating a station from as scheduled start time or manual operation, approximately 28.4 volts AC can be measured across terminals L1/L2.   Confirm AC voltage on the Hunter ICC “power module” AC terminals that should be the same voltage.  

Voltages less than 24 VAC will indicate an incorrect seating of the Decoder Module or inadequate hardwire connection to the Hunter ICC controller and/or a defective internal transformer.  Troubleshoot and repair as needed.

Each decoder must be pre-programmed with a corresponding station number.  This is accomplished by inserting the red and black decoder wires into the corresponding colored, spring-loaded terminals above the ground lug on the Decoder Module.  The programming or addressing of a decoder is a two-step process and instructions are included with each module or found on the Underhill website. 

A decoder may also be programmed from an Underhill Portable Programmer in one of three product offers:
•	DEC-PROG-115 – w/ 115V power supply
•	DEC-PROG-240 – w/ 240V power supply
•	DEC-PROG-12 – w/ 12V power inverter

Operation 
When an ICC 2Wire Decoder Module is installed, it will execute all programming functions of the Hunter ICC controller.   The ICC Decoder Module is only compatible with Underhill single-station decoder p/n TW-TK-DEC-1.  

When incorporated with a normally closed master valve, the installer has the following two options
1)	Install a separate two conductor wire path between the controller and the master valve separate from the 2Wire module or, 
2)	Install a decoder with the master valve and program the decoder as the first or last station.  The ICC controller automatically actuates the master valve each time a station is operated from a scheduled start or manual station operation.  

!

Note:  Wire sizing and distance between the controller and the master valve should be considered as part of option #2.  See Underhill’s web site for recommended wire sizes and maximum wire lengths. 

The ICC 2Wire Decoder Module will illuminate a red LED Error when a field fault occurs.  This field fault can be one of several field conditions listed as:
•	A valve solenoid that has reached end of life and drawing too much current,
•	A faulty decoder, 
•	A faulty wire splice where the resistance exceeds the limits of the 2Wire module or,
•	A broken wire(s) in the 2Wire path.

Methods to troubleshoot each one of the identified field faults can be found on the Underhill web site per the following web link;

http://underhill.us/library/downloads/viewdownload/90-troubleshooting/1061-troubleshooting-2wire-systems

The Underhill ICC 2Wire Decoder Module is warranted for a period of 2-years from the date of purchase.  Underhill warrants the product when properly grounded per the Installation Instructions as it will vary depending on where the ICC Decoder Module is installed. 

The Underhill ICC 2Wire Decoder Module shall be distributed and supported by Underhill International Corporation, Mission Viejo, CA.