Do-more H2 Series PLC User Manual, 1st Edition, Rev. F - H2-DM-M
8–5
Chapter 8: Installation and Wiring
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
Emergency Power Disconnect
A properly rated emergency power disconnect should be used to power the PLC controlled
system as a means of removing the power from the entire control system. After an emergency
shutdown or any other type of power interruption, there may be requirements that must be
met before the PLC control program can be restarted. For example, there may be specific
register values that must be established (or maintained from the state prior to the shutdown)
before operations can resume. In this case, you may want to use retentive memory locations, or
include constants in the control program to insure a known starting point.
Orderly System Shutdown
Ideally, the first level of fault detection is the PLC control
program, which can identify machine problems. Certain
shutdown sequences should be performed. The types of
problems are usually things such as jammed parts, etc. that
do not pose a risk of personal injury or equipment damage.
WARNING: The control program
must not
be the only form of
protection for any problems that may result in a risk of personal
injury or equipment damage.
Class 1, Division 2, Approval
This equipment is suitable for use in Class 1, Division 2, Zone 2, groups A, B, C and D or
non-hazardous locations only.
WARNING: Explosion Hazard! Substitution of components may impair suitability for Class 1, Division 2,
Zone 2.
WARNING: Explosion Hazard - Do not disconnect equipment unless power has been switched off or the
area is known to be non-hazardous.
WARNING: All Do-more products used with connector accessories must use R/C (ECBT2) mating plugs.
All mating plugs must have suitable ratings for the devices.
Turn off
Saw
Jam
Detect
RST
RST
Retract
Arm
