Rockwell Automation 2727-G7P20D3Q7 MobileView G750 Guard Machine Terminal - Manual (Page 21)

Publication 2727-UM002D-EN-P
Safety Precautions and Elements 2-3
Power Supply
Enabling Switches The enabling switches are in accordance with EN 60204-1 in safety
categories according to EN 954-1 (Safety related parts of control
system). There are two parallel switched, potential-free, normally
open contacts for connecting external peripherals, nominal voltage
24V dc (safety-extra-low voltage in accordance with EN 61131-2 and
EN 50178), typical current 500 mA dc.
The electronic enabling switch realizes the enabling equipment as a
safety function for machines in special operating modes. The enabling
switch is part of the MobileView terminal.
Each machine features a normal operating mode and a special
operating mode.
• In normal operating mode, guards and/or operative protection
devices are used to prevent access and guarantee safety. Special
operating modes are used to maintain the normal operating
mode.
ATTENTION
!
• The device meets the safety class III in
accordance with EN 61131-2 and EN 50178. The
24V power supply for the equipment must
provide appropriate isolation between the
safety-extra-low-voltage circuits and
dangerous-contact voltage circuits (for example,
by safety transformers or similar facilities).
• The power supply circuit must be protected with
a 3.15 A fuse.
• The nominal supply voltage of the MobileView
terminal (without MobileView Connection Cable)
is 24V dc (supply voltage range: 18-32V dc).
• Typical current consumption is:
- 300 mA at 24V dc
- 400mA at 18V dc
• When planning the power supply, consider the
voltage drop in the connection cable.
Specifications of power supply lines in the
connection cable are:
- Cross section: AWG24 (0.24mm2)
- Material: zinc-coated copper strand
- Line resistance: <90 Ohm/km (<145 Ohm/mile)