2 Engineering
2.10 STO function
70
DA1 Variable Frequency Drives
08/18 MN04020005Z-EN
www.eaton.com
2.10.4 STO-compatible installation
DANGER
Make sure to use proper earthing and select cables based on
local regulations or standards.
The variable frequency drive may have a leakage current greater
than 3.5 mA AC or 10 mA DC. In addition, the grounding cable
must be sized for the maximum mains fault current, which is
normally limited by fuses or miniature circuit-breakers.
Appropriately sized fuses or miniature circuit-breakers should be
installed at the mains supply for the variable frequency drive in
line with local regulations or standards.
DANGER
The “STO wiring” must be protected against unintended short-
circuits and unintended tampering and modifications.
It must be ensured that the "STO input signal" (control signal
terminals 12/13) has a safe operating state.
CAUTION
Variable frequency drives with IP 20 protection that are used in
environments with a pollution degree of 2 must be installed in a
control panel with IP 54 protection or better.
￫
In order to prevent damage to the variable frequency drive, the
devices should remain in their original packaging until right
before they are installed.
They must be stored in a dry and clean area with a temperature
range of -40 °C to 60 °C.
￫
The conductor cross-section used for the STO installation
should be between 0.05 and 2.5 mm
2
(AWG 30-12).
The length of the cable connected to the control signal terminals
should not exceed 25 meters.