Siemens Maxum II Manual page 15

Failure to adhere to the instructions and requirements below could violate the safety
protections of the analyzer.
Maintenance Considerations for Intrinsically Safe Devices:
● Maintenance for intrinsically safe devices, such as the IS-TCD, is limited to replacement.
Repair or service on-site are not permitted.
● Intrinsically safe devices in the Maxum II that are equipped with a cover must have the
cover attached during use. Leaving the cover off can violate requirements pertaining to
mandatory separation from non-IS wiring.
● Intrinsically safe devices in the Maxum II must be operated with all factory installed
mounting and grounding hardware secured. IS circuitry within the Maxum requires two
redundant chassis grounds. There are two separate grounding connections from the CIM-
Base and the IS-TCD to the chassis. Note that redundant grounds from the same device
may not be stacked on the same termination point, but grounds from different devices (such
as CIM and IS-TCD), may share a termination point.
● Care must be taken to prevent other wiring from contacting the IS circuitry. This means that
other all wiring that is secured must remain secured. If it becomes necessary to unsecure
wiring for maintenance, then the wiring must be secured again before placing the equipment
back in service.
● External wiring includes serial cabling, Ethernet cabling, external IO wiring, external power,
and any other wiring that enters the Maxum enclosure from outside. For the installation of
any external wiring, the wiring must be secured in a minimum of two locations, within 50mm
of its termination point and also within 100mm of its termination point. Additionally, secure
along its length as needed to prevent it possibly coming within 50mm of any IS circuitry.
● Any wiring that is not sufficiently secured per the above requirement must have sufficient
insulation thickness to add up to at least 1mm of solid insulation, 2mm of encapsulation, or
remain on the opposite side of a suitable physical barrier from any IS circuit.
● The Maxum chassis is required to be earth grounded at the location where it is installed
using ground screws connected externally as described in the Maxum Installation Manual
(2000595‑001). The earth ground used must be as close to the Maxum as possible.
● Power system ground, from mains power that is brought to the Maxum, is required to be
grounded to the cabinet as part of required installation practices for basic safety.
Explosion Protection Safety Standards
Manual, August 2017, A5E02220442001 Rev 8
CAUTION
General Information for the User
1.6 Intrinsically Safe Devices
15