Ion Science TVOC - Manual (Page 14)

TVOC MANUAL Ion Science Ltd
Page 14 of 32
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Installation
– Hazardous location
Warning!
The label on the enclosure details the IS and nA certifications. The appropriate section of the Intrinsically
Safe label should be covered up or blocked out to reflect the type of installation. For Non-intrinsically Safe
applications the label should be covered completely. For Intrinsically Safe (IS) Zone 2 applications with out
safety barriers the ia certification details should be blanked out. For Zone 1 or Zone 2 IS applications with
safety barriers the nA certification details should be covered. This will prevent safety discrepancies and or
mis-use in the future should the equipment be moved or the site be re-defined as a hazardous area.
Entry parameters for intrinsically safe Zone 2, nA (non-sparking) areas only:
Input power
5-24 Vdc, 80 mA max
Output power (4-20 mA) 8-35 Vdc, 22 mA
For information only: please see Intrinsically Safe operation certificate before installation.
The wiring of Intrinsically Safe systems is identical to the wiring showing for non Intrinsically Safe
applications. The only difference is the requirements to ensure that the power supplied used provides 24 V or
less in normal operation.
Intrinsically Safe (IS) applications:
Entry parameters
Input power Ui = 18V Ii = 800mA Pi = 1.2W Ci = 0

F Li = 0mH
Output power(4-20mA) Ui = 30V Ii = 200mA Pi = 1.2W Ci = 0

F Li = 0mH
For information only please see Intrinsically Safe certificate before installation
Ion Science Ltd suggest using the following zener barriers for IS approved applications. Use competent
installation engineers and ask them for installation and application advice.
Note

All cable lengths are estimated for Zone 1 IIC installation of the equipment

Using 1 mm
2
C.S.A conductor S.T.P cables with capacitance per meter of 250 pF/m, L/R ratio of 25
muH/

conductor resistance at 20

C of 18.4

/km.

Calculation assumes cables are at 50

C.
Warning! Intrinsically Safe (IS) applications

Units should not be powered using non IS power supplies prior to installation in an IS application.

If non IS power is supplied the unit will require inspection by Ion Science Ltd or an Ion Science Approved
Service Centre prior to installation in an IS application.

TVOC fuses may not be replaced in the field.

If a fuse is blown TVOC will require inspection by Ion Science Ltd or and Ion Science Approved Service
Centre before it is used in an IS application.