AccuLoad IV Installation & Maintenance Manual
Installation
17
•
Sufficient slack should be provided for the wiring in the AccuLoad to permit easy removal of the
boards. With sufficient slack, the terminal blocks can be removed and laid out of the way so that the
boards can be replaced without removing individual wires.
•
A ground lug is provided in the unit; the wire from the lug should be connected to the proper grounding
Section 2.5: Electrical Installation Considerations
for more information).
•
Typical installation diagrams are provided in the following sections to show the electronic connections
between the AccuLoad and compatible electronic modules. Before wiring any ancillary equipment,
refer to its product-specific installation manual.
3.2 ATEX- and IECEx-Approved Installations
The following sections contain information about installing models ST and QT, which have explosion-proof
enclosures.
3.2.1 Installation
General Installation should be in accordance with IEC 60079-14; the wiring system should be in
accordance with Section 9 of IEC 60079-14.
3.2.2 Hazard Warnings
To prevent the ignition of hazardous atmospheres, disconnect from the power supply before opening the
enclosure. Keep the enclosure tightly closed when circuits are alive.
The AccuLoad contains internal battery-powered circuits; to prevent the ignition of hazardous
atmospheres, do not open its enclosure unless the area is known to be non-hazardous. To reduce the risk
of ignition of hazardous atmospheres, conduit runs must have a sealing fitting connected within 18 inches of
the enclosure. Substitution of components may impair intrinsic safety.
3.2.3 Special Conditions for Safe Use
Special conditions for safe use include:
•
Wiring and cable glands should be suitable for operation at 81 °C.
•
Flame path dimensions for flanged joint widths must be a minimum of 19.05 mm. The clearance
between flat joint surfaces must be less than 0.05 mm (0.002 inch) or such that a (0.002 inch) feeler
gauge cannot enter the joint more than 3.2 mm (0.125 inch) at any point. Flame-proof joints should be
maintained as outlined in Section 10.4 of IEC 60079-14.
3.2.4 Cable Entries
Cable entries must be in accordance with IEC 60079-1 section 13, as follows:
The maximum ambient temperature for the enclosure is 60 °C for ATEX and IECEx applications and
55 °C for North American Zone applications.
Summary of Contents for Smith Meter AccuLoad IV
Page 7: ...AccuLoad IV Installation Maintenance Manual Introduction 2 Figure 1 AccuLoad IV ST ...
Page 9: ...AccuLoad IV Installation Maintenance Manual Introduction 4 Figure 3 AccuLoad IV QT ...
Page 11: ...AccuLoad IV Installation Maintenance Manual Introduction 6 Figure 5 AccuLoad IV N4 ...
Page 14: ...AccuLoad IV Installation Maintenance Manual Introduction 9 Figure 8 AccuLoad IV SA FCM ...
