Crysberg system installation guide

The Crysberg AquaLogic 500 is a two-wire decoder system: a single red/black cable leaves the controller and 2-wire runs past every device in the field. Rather than running a dedicated cable back to each valve, each decoder simply taps into the shared two-wire line and is addressed individually by the controller — so one cable run can drive an entire site.

The diagram above shows a typical layout. The Crysberg controller sits at the top of the line. Along the cable, Output Decoders drive irrigation solenoids, an Input Decoder reads the flow sensor, and other decoder types handle additional functions. The detail circle shows how a decoder connects: each wire is tapped with a wire nut* so the two-wire line continues unbroken to the next device.

This guide walks through wiring each decoder type onto the two-wire line, one step at a time.

We recommend using wire nuts* rated for direct burial (gel-filled / waterproof connectors) at every tap, and cable that is jacketed solid parallel wire for the two-wire line. This keeps connections sealed against moisture and ensures reliable long-term operation in the field.

For more information, see the Decoder guidelines document.

How it connects (see schematic above)

The Aqualogic has a dedicated grounding terminal. Run a 6 AWG / 4 mm2 wire from this terminal down to a grounding rod / plate driven into the soil close to the Aqualogic. Keep the run as short and as straight as possible — every bend adds impedance and reduces surge performance. The Aqualogic also need to be grounded for corrosion purposes. The resistance to the ground must be 10 Ω or less.

Do not connect the Aqualogic earth terminal to the mains protective earth (PE).

Steps

1. Locate the ground terminal on the Aqualogic.
2. Drive a grounding rod / plate into the soil close to the Aqualogic.
3. Run a 6 AWG / 4 mm2  wire from the earth terminal to the grounding rod / plate, and secure it with a proper earth clamp.
4. Keep the earth wire as short and straight as possible.
5. Do not bond this terminal to the mains protective earth (PE).

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past the decoder, and on to the next decoder in the line. The decoder simply taps into it.

The FD101 has two blue wires on its input side. Each blue wire is joined the 2-wire cable — one blue to red, one blue to black — so the decoder draws from the 2-wire cable in parallel while the 2-wire cable continues. On the output side, the FD101's two white wires connect to the valve's solenoid.

Steps

1. Run the red/black two-wire cable down from the controller terminal.
2. Wire nut* 1 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the FD101.
3. Wire nut* 2 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the FD101.
4. Connect the FD101's two white wires to the solenoid valve. Check polarity first (see note below).
5. Carry the red/black 2-wire on to the next decoder. If this is the last decoder on the line, terminate the 2-wire with a LSP decoder connected to a grounding rod/plate.

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past each decoder, and on to the next decoder in the line. Both the FD101 and the LSP simply tap into the 2-wire cable in parallel.

The FD101 taps the 2-wire cable through wire nuts* 1 & 2 and drives an solenoid valve from its white wires, exactly as in section 2. The LSP surge decoder taps through wire nuts* 3 & 4, and instead of a valve it runs two yellow/green protective-earth wires to a grounding rod/plate.

Steps

1. Wire the FD101 decoder as in section 2 — wire nuts* 1 & 2, blue wires to the decoder, white wires to the solenoid valve.
2. Carry the red/black 2-wire cable to the LSP location.
3. Wire nut* 3 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the LSP.
4. Wire nut* 4 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the LSP.
5. Connect the two yellow/green output wires from the LSP decoder to the grounding rod/plate. If there is a nearby valve in a conductive metal, then one of the green/yellow wires can be connected to the valve to create an alternative surge path.
6. Carry the red/black 2-wire cable on to the next decoder. If this is the last decoder on the line, terminate the 2-wire instead with the LSP decoder connected to a grounding rod/plate.

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past the decoder, and on to the next decoder in the line. The Multi output decoder simply taps into it through two wire nuts*, exactly like the FD101.

The difference is on the output side: a single Multi output decoder has its own 1-6 different cables that drives between 1 and 6 solenoid valves from individual colored station outputs, and runs a twisted yellow/green wire to a grounding rod/plate.

Steps

1. Run the red/black 2-wire cable down from the controller to the decoder location.
2. Wire nut* 1 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the Multi output decoder.
3. Wire nut* 2 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the Multi output decoder.
4. Run an individual colored set of cables from each output channel on the Multi output decoder to its solenoid valve (1–6 valves total). Check polarity first (see note below).
5. Connect the twisted yellow/green wire from the Multi output decoder to the grounding rod/plate.
6. Carry the red/black 2-wire on to the next decoder. If this is the last decoder on the line, terminate the 2-wire. Since the surge protection is built into the Multi output decoder it can be terminated with this connected to a grounding rod/plate.

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past the decoder, and on to the next decoder in the line. The Easyguard simply taps into it through two wire nuts*, exactly like the FD101.

On the output side the Easyguard is a mix of the two earlier decoders: a single white cable runs to the solenoid valve, just like the FD101, and a twisted yellow/green wire runs to a grounding rod/plate, just like the LSP. The surge protection is built into the decoder, so no separate LSP is needed at this point.

Steps

1. Run the red/black 2-wire cable down from the controller to the decoder location.
2. Wire nut* 1 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the Easyguard.
3. Wire nut* 2 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the Easyguard.
4. Run the white station cable from the Easyguard output to the solenoid valve.
5. Connect the twisted yellow/green wire from the Easyguard to the grounding rod/plate.
6. Carry the red/black 2-wire on to the next decoder. If this is the last decoder on the line, terminate the 2-wire. Since the surge protection is built into the Easyguard it can be terminated with this connected to a grounding rod/plate.

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past the decoder, and on to the next decoder in the line. The decoder simply taps into it through two wire nuts*, exactly like the FD101.

The SD110 has two blue wires on its input side. Each blue wire is joined the 2-wire cable — one blue to red, one blue to black — so the decoder draws from the 2-wire cable in parallel while the 2-wire cable continues. On the sensor side, the SD110 has a red and a black wire, and the sensor will useually have a matching red and black cable.

Steps

1. Run the red/black two-wire cable down from the controller terminal.
2. Wire nut* 1 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the SD110.
3. Wire nut* 2 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the SD110.
4. Connect the SD110's red and black wires to the sensor's red and black cables — red to red, black to black, each joined with a wire nut*.
5. Carry the red/black 2-wire on to the next decoder. If this is the last decoder on the line, terminate the 2-wire with a LSP decoder connected to a grounding rod/plate.

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past the decoder, and on to the next decoder in the line. The decoder simply taps into it through two wire nuts*, exactly like the FD101.

The SDI-12 has two blue wires on its input side. Each blue wire is joined the 2-wire cable — one blue to red, one blue to black — so the decoder draws from the 2-wire cable in parallel while the 2-wire cable continues. On the sensor side, the SDI-12 has a red, a black and a white wire — supply, ground (GND) and data, respectively. The sensor will have a matching supply, ground and data cable.

Steps

1. Run the red/black two-wire cable down from the controller terminal.
2. Wire nut* 1 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the SDI-12.
3. Wire nut* 2 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the SDI-12.
4. Connect the SDI-12's supply, ground and data wires to the sensor's supply, ground and data cables — supply to supply, ground to ground, data to data, each joined with a wire nut*.
5. Carry the red/black 2-wire on to the next decoder. If this is the last decoder on the line, terminate the 2-wire with a LSP decoder connected to a grounding rod/plate.

How it connects (see schematic above)

A 2 wire — one red wire, one black wire — runs down from the controller, past the decoder, and on to the next decoder in the line. The decoder simply taps into it.

Unlike the FD101, the DIN 101 has no pre-mounted cables — all connections are made to screw terminals on the module. On the input side, two blue wires are run from the screw terminals and joined to the 2-wire cable — one blue to red, one blue to black — so the decoder draws from the 2-wire cable in parallel while the 2-wire cable continues. On the output side, two white wires are run from the screw terminals on the right side of the module to the valve's solenoid.

Steps

1. Mount the DIN 101 on the DIN rail.
2. Run the red/black two-wire cable down from the controller terminal.
3. Wire nut* 1 — join three wires: the incoming red 2-wire, the red 2-wire continuing, and one blue wire from the DIN 101.
4. Wire nut* 2 — join three wires: the incoming black 2-wire, the black 2-wire continuing, and the other blue wire from the DIN 101.
5. Connect the DIN 101's two white wires to the solenoid valve. Check polarity first (see note below).
6. Carry the red/black 2-wire on to the next decoder. If this is the last decoder on the line, terminate the 2-wire with a LSP decoder connected to a grounding rod/plate.