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Chapter 2   Installation 
Power Supply Requirements 
Ultra 3 can operate from AC supply or from a DC battery and is designed 
for use in temperatures between -4
o
F to +140
o
F (-20
o
C to +50
o
C). The AC is 
115V +5% / -10% 50/60Hz. The DC is 18-30V. In all cases the Ultra 3 will 
typically consume 6W of power, with a maximum of 10W. If Ultra 3 has 
both  an  AC  and  DC  supply available  then  the  AC  supply source  will  be 
automatically sensed and used, should the AC supply be removed for any 
reason then the DC supply will take over. 
The  AC  and  DC  wiring  should  be  completed  using  either  16  –  14AWG 
(1.5–2.5mm
2
)  stranded  or  16  –  14AWG  (1.5–4mm
2
)  solid  wire,  with  all 
terminals being tightened to 4.5in. lbs. (0.5Nm). 
An external supply isolator/circuit breaker (AC or DC) must be fitted near to 
the unit and labelled to identify the instrument to which it refers. 
Safety Symbols 
Detailed  below  are  descriptions  and  meanings  of  safety/warning  symbols 
that are used on the Ultra 3 and in this manual.