Purpose
In the process of Humidity-freeze test and thermal cycle test, It can real time measure and record the voltage, current and temperature, and also can determine the internal circuit continuity

Reference
IEC61215-2005 Crystalline silicon terrestrial photovoltaic (PV) modules-design qualification and type approval
GB6587.7-1986 Electronic measurement equipment fundamental safety tests
GB17478-1998 Low-voltage DC power supply devices output-Performance characteristics and safety requirements

System Scheme
The power supply group scheme is the network of OMRON PLC and RS485 BUS.
1. Upper computer-PLC Communication.
2. With Power supply RS-485 communication port, PLC can exchange data with power supply via RS-485 BUS without PLC I/O module transformation.
3. Controllable items by RS285: constant voltage, constant current, voltage, current; Feedback data: constant voltage state, constant current state, fault state, voltage value, current value.
4. Controllable items by PLC : start-up state, stop state; Feedback data: Start-up state , stop state.
5. PT100 signal via PLC by temperature transmitter to finish temperature sampling.

Hardware Specifications
DC Power supply channel number and fundamental requirements
Input Voltage: AC220V   50Hz
Output Voltage: DC 0-80V
Current Range: 0-15A ,6 channels
Display: 80V 15A
Communication RS485: 6 Channels, potential control and collection of Voltage and current
Potential control: 6 channels, switch signal output (controlling on-off of constant current)
Collection: 1-channel, temperature collection
Protection: overcurrent protection, overvoltage protection, overload protection , overheat protection.
Output: connection terminal output at the back of machine.

Advantech IPC
4U Standard cabinet / 300 W Power / 14S4 bottom panel, memory / 300G Hard disk /DVD-ROM drive / one parallel port and one serial port / Genuine Windows system / 19’’ keyboard / 17’’ LCD / PT100 Pt Resistance
The implementation standard is (china's machinery industry standard) JB T 8622-1997, which conforms to IEC751: the formula of resistance versus temperature and Reference tables in 1983, measurement range -50℃—110℃ with tolerance level ±0.5℃

1. With upper computer, set, record and store output voltage, current and temperature.
2. In manual state, set the voltage of 6 channel power, power and the limit temperature of relevance power
3. Display and record the voltage ,current and temperature of each channel
4. Easily export the historical power output voltage, current and temperature curve
5. Voltage display ：80V current  15A
6. One-channel environmental temperature input ( Using PT100 Pt-Resistance, temperature range -50℃—110℃).
7. The computer can set the limit of overcurrent, overvoltage, overtemperature in order to stop the output beyond the limit.
8. Provide the alarm of abnormal information in reverse electrifying process of Solar cell components so that field staff can timely check it.
9. Communicate state is displayed in software by display light. Green light means normal state and Red light means abnormal state.
10. After deal halt, just restart the software and no need to restart power and computer
11. All measurement curves with the function of period finding and period searching

System Telecommunication BUS
1. PLC to Power, using supply free protocol communication via COMI of PLC to realize the setting of Voltage and current and reading the feedback of Voltage and current.
2. PC to PLC, using Siemens AG PLC to collect data.

Software Running Environment
IPC operating system is Genuine MICRSOFT WINDOWS XP PROFESSIONAL SP2 system.  The power is controlled by PLC, and IPC is only for Human-machine Interface to input, monitor and record data, but not for actual control. Upper computer software is WINCC6.0, PLS data collection system is OMRON OPC SERVER. This Configuration is being used in many power supplies in my company.