Menu Structure

1.0 Operation Mode	1.1 left to escape, right to continue	to prevent accidental mode switching
	1.2 User Mode ELC IGC Protection Relay User Load Output Test	1. for sychronous Generators 2. for Induction Generators 3. emergency fault shutdown 4. automatic user load warning and switching 5. Output Test Mode switches all outputs on,     regardless of input values
	1.3 single phase/3phase
	1.4 up one level
2.0 Input Readings	2.1 Hz
	2.2 AC Volts L1 L2 L3
	2.3 DC Volts	for checking a backup battery to operate the water valves in case of power outage
	2.4 current amps
	2.5 Dump load percentage	how much of the dumpload is currently on
	2.6 shutdown reason
	2.7 total operating days	while all values are in range. write to eeprom every day and while shutdown
	2.8 operating days since last shutdown	"
	2.9 reset total operating days
	2.10 one level up
3.0 Range Settings		For fault detection
	3.1 minimum frequency
	3.2 maximum frequency
	3.3 Minimum AC Voltage
	3.4 Maximum AC Voltage
	3.5 Minimum DC Voltage
	3.6 Maximum DC Voltage
	3.7 maximum amps
	3.8 delay time	for how long must the value be permanently out of range to trigger shutdown
	3.9 up to top menu
4.0 ELC/IGC Settings	4.1 ELC: target frequency	50 or 60 Hz
	4.2: IGC: target voltage	220, 230, or 240 Volt (depending on your country)
	4.3 P-Value	see here
	4.4 I-Value
	4.5 Valve ON /secs	in case the valves operate very quickly, one can specify a run (ON) / wait (OFF) time here to slow the change rate down and avoid oscillation
	4.6 Valve OFF /secs
	4.7 up to top menu
5.0 Protection Relay	start up/fault reset	Main relay/connector will be released as soon as all values are in the green range. If there is a water valve relay, it will be released even if there is no Mains Voltage.
6.0 User Load Settings
	6.1 Back on Voltage	hysteresis, after user load has been disconnected
	6.2 Back on frequency	hysteresis, after user load has been disconnected
	6.3 delay time before off	The first relay will switch immediately, this can be use for a warning signal. The second relay will switch after the time specified here.
	6.4 delay time before back on	This gives the users time to disconnect appliances before the cotroller tries to reconnect.
	6.5 overload warning signal	When activated, this will regularly switch on some dumpload in case of underfrequency/undervoltage. the resulting frequency drop will change the sound of the hum in user appliances. If they hear this, they should switch off loads.
	6.6 up one level
7.0 Calibration		Adjust meter readings
	7.1 Line 1 correction factor
	7.2 Line 2 correction factor
	7.3 Line 3 correction factor
	7.4 DC correction factor
	7.5 Amps correction factor
	7.6 P-I Auto Tuning	not implemented
	7.7 software/hardware version	mention this in communication for problem tracing
	7.8 up one level

What is an ELC?

Electronic Load Controller.

This site has moved to www.hydroelectronics.net

Controllers are available for order on the new site.

In order to make the power of your generator useable, you need to make sure the voltage (Volts) and the frequeny (Hz) stay stable.  List of worldwide mains voltages and frequencies.

The AVR Automatic Voltage regulator takes care of the voltage.

The ELC takes care of the frequency.

Principle: 

The higher the user load, the lower the frequency will get. So if you switch on the kettle, the frequency will drop. The ELC does nothing more than switching off an equal amount of power (wattage), so the frequency stays stable even after you've switched on the kettle.

So in effect, the total amount of power consumed always stays the same.

To ensure this switching works as smooth as possible, the ELC uses a Proportional-Integral feedback loop, PI-Controller

This site has moved to www.hydroelectronics.net

Controllers are available for order on the new site.

Overspeed

Why is overspeed dangerous for the generator?

Especially with bigger systems, the generator is not rated for much more speed than the operational speed. Check your generator ratings.
If, say, the AVR (Automatic voltage regulator) or the excitation system fails, there will be no load on the turbine, and the generator will speed up. The centrifugal force will loosen the wire windings of the generator and tear them apart.

Tools used

Programming 

Flowcode for Picmicro and Eblocks Development kit

The development board can program the Picmicro chip.
Product Link
(I used Version 4.5)
Obviously you need a computer with USB to use the kit.

Printed Circuit Board

Open Source Schematics and PCB layout program KiCad (great prorgram, and here is a great tutorial)

Bill of Materials

External 5V Power supply

Minimum 1A (= 5W)

Why not an internal Power supply?

• I can't build a high quality AC/DC power supply for the price of a comparable commercially readily available product.
  You can use any type, just make sure it's got protection features and a regulated output. A cheap unregulated mains plug adapter probably won't work.
• The power supply is easier to replace or reuse, if it's not all on the same PCB board.
• You can decide to operate the Protection Relay from a DC source - simply use a DC/DC power supply.This might be the case if motorized water valves should close if there is no AC supply for whatever reason.
  

Examples

http://www.conrad.de/ce/de/product/514428/Dehner-Elektronik-SYS-1319-2005-T3-Tischnetzteil-5-VDC-4-A-20-Watt/2110212&ref=list
(Don't make the DC cable too long)

If there's a power socket nearby, you can use this:
http://www.conrad.de/ce/de/product/512723/Dehner-Elektronik-SYS-1381-1005-W2E-EURO-Steckernetzteil-Steckernetzgeraet-5-VDC-2000-mA-10-Watt/2110120&ref=list

If you like to include the power supply in the main case, use something like this:
http://www.conrad.de/ce/de/product/512731/TDK-Lambda-LS25-5-Einbau-Netzteil-5-VDC-5-A-25-W/2110485&ref=list

Solid State Relay SSR

Why not use internal triacs? With an earlier version, I used internal triacs, but they need to be mounted on a heatsink, and the heatsink carries line voltage, and if they fry, it's a pain to replace them.
External SSRs are much easier to handle: easily replaceable for different sizes of dump loads, no external parts carrying line voltage.
Just make sure you use SSRs with high voltage isolation between control voltage and switch voltage. Types with an LED are good for installing and monitoring, because you can see their switch state.

Zero crossing types are fine. With Random Turn-On Solid-State Relays, also known as “asynchronous” or
“instantaneous” types, you can control the frequeny a bit better (phase angle control), but at the price of distorting the waveform and producing HF noise, especially with low power systems combined with big dumploads.
Here's a pdf explaining the difference between zero crossing and random types
Alternative link

Also make sure you use a heat sink, if you want to use the SSR to its full rating.

The ELC outputs a control voltage of 4V, max. 300mA. So any SSR with a control input of 4V DC or less is suitable.

Ebay carries loads of them.
SSR example     Heat sink example 1   Heat Sink example 2


Case - suitable for a 160 x 100 mm PCB Printd Circuit board
Hammond Electronics BOXE


Microcontroller Unit MCU : PIC16F1939
http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en538148