The Shamrock series are powered by external PSUs- details for each model are shown in the table below. 
Parameter 500i 750
Mains Power Supply 
Requirements
100 - 240 V AC, 47 - 63 Hz
PSU Output 24 VDC, 2.5 A
Power Connector 
Type
KPPX 4-pin
Pins 1 & 2: + 24V
Pins 3 & 4: 0V
NOTES:
1.   The electrical mains lead should be certied for use in your country and in applicable countries the plug must be 
tted with a 240V 5A fuse.
2.   If users use any other power supply, they do so at their own risk.
3.   The Shamrock series of spectrographs is for use with Telecommunications, Computer, Industrial Controller, and 
OA Systems and must only be used indoors.
4.   Shamrock spectrographs require a Direct Current (DC) supply.