ChemoMetec NC-250 - Manual (Page 13)

Warnings and precautions
991-0251 Rev. 1.0 Feb-2013 xiii
Warnings and precautions
Whenever the symbol appears on the NucleoCounter® NC-250™ instrument, it
indicates that the manual must be consulted for prec autions and warnings.
Power and cables
Use the shielded USB cable supplied with the NucleoCounter® NC-250™ to ensure that
appropriate EMI classification is maintained for the intended environment.
The USB interface connector of the NucleoCounter® NC-250™ must only be connected
to SELV circuits. External computing devices connected to the USB interface connector of
the NucleoCounter® NC-250™ has to comply with the standards, UL 1950 and IEC/EN
60950.
Table 1. Description of the NucleoCounter® USB interface connector
NucleoCounter® NC-250™ is powered by an external 24VDC power supply. For safe use,
please follow the instructions for connecting the power supply.
The NucleoCounter® NC-250™ shall only be used with an external power supply
purchased at ChemoMetec A/S.
The detachable DC power supply cord set and appliance inlet of the external power
supply are considered as the disconnecting device.
The mains supply cord and plug of the external power supply shall comply with any
national regulations.
1
In normal operation mode (refers to Pin no 4)
Pin no. Name
Maximum
Voltage level
1
1 +5V +5 VDC
2 D- +3.5 VDC
3 D+ +3.5 VDC
4 DGND 0 VDC
Metal
enclosure
Shield
(connected
to DGND)
0 VDC