Siemens Simatic S7-400 - Manual (Page 51)

General Technical Specifications
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
1-23
Maintenance
If repair is necessary, the affected module must be sent to the production location.
Repairs can only be carried out there.
Special Conditions
1. The SIMATIC S7-400 must be installed in a cabinet or metal housing. These
must comply with the IP 54 (in accordance with EN 60529) degree of protection
as a minimum. The environmental conditions under which the equipment is
installed must be taken into account. There must be a manufacturer's
declaration for zone 2 available for the housing (in accordance with EN 50021).
2. If a temperature of > 70 °C is reached in the cable or at the cable entry of this
housing under operating conditions, or if a temperature of > 80 °C can be
reached at the junction of the conductors under operating conditions, the
temperature-related properties of the cables must correspond to the
temperatures actually measured.
3. The cable entries used must comply with the required IP degree of protection
and Section 7.2 (in accordance with EN 50021).
4. All devices (including switches, etc.) that are connected to the inputs and
outputs of S7-400 systems must be approved for EEx nA or EEx nC explosion
protection.
5. Steps must be taken to ensure that the rated voltage through transients cannot
be exceeded by more than 40 %.
6. Ambient temperature range: 0° C to 60° C
7. A sign containing the following warning must be put up inside the housing in an
easily visible position when the housing is opened:
Warning
The housing can only be opened for a short time (e.g. for visual diagnostics). If
you do this, do not operate any switches, remove or install any modules or
disconnect any electrical cables (plug-in connections).
You can disregard this warning if you know that the atmosphere is not
hazardous (i.e. there is no risk of explosion).
List of Approved Modules
You will find the list of approved modules under the ID 13702947 on the Internet:
http://www4.ad.siemens.de/view/cs/ .