Ampcontrol CSM Pty Ltd -
ABN 35 000 770 141
ECD User Manual
Rev 3 – March 2020
ECDB005R0
13/03/2020 13:12
Page 13 of 21
Wherever a screened cable is to be connected to Earth, ensure that the screen is
earthed at ONE END ONLY, as near to the ECD as practicable.
4.2.1
Supply
The appropriate power supply is dependent on the ECD model. The ECD relay is available as either a 24Vdc ±20% or as a
48V
dc ±20% model.
4.2.2
Pilot Terminal
The pilot terminal is an IS terminal (protected by an internal IS barrier) through which the ECD performs resistance
measurements.
Typically the pilot terminal will be connected to the pilot conductor of a trailing or reeling cable. The load end of the pilot
conductor will then be terminated with a diode to earth, creating a return path through the earth conductors of the cable to the
main earth point of the outlet and then to the ECD’s IS earth terminals. The primary function of the ECD relay is to verify the
resistance of this pilot earth-loop is below a selectable level.
4.2.3
IS Earth Terminals
The IS earth terminals provide the earth connection for the ECD’s internal IS barrier as well as the earth reference for the pilot
resistance measurement. These terminals must be connected directly to the outlet’s main earth point by 3 x 1.5mm2 cables
. No
other connections are permitted.
4.2.4
Reset - Optional
This is an active high input that allows ECD trips to be reset in latching mode, after the fault has been cleared. The reset input
has no affect in non-latching mode.
The Reset input should be connected to the ECD’s ‘+’ terminal via a normally open switch with a minimum rating of the supply
voltage.
4.2.5
Relay Contacts
The default position of the relay contacts (Normally Open or Normally Closed) is described on the ECD front label and
Figure 3
.
The relay contacts will change state when the ECD is started (Status LED flashing) and will return to the default state when the
ECD “trips”.
The relay contacts are rated for 1A @ 110Vac and 1A @ 30Vdc (Resistive).
4.2.6
External Fuse
The ECD’s IS Pilot Terminal is protected by an internal IS barrier. In the event of a phase to pilot fault this barrier will clamp the
voltage at the pilot terminal to a safe level and protect the relay
from damage. However this barrier can only withstand 5.25A for
1s. The ECD relay must
, therefore, be installed in a system with earth fault current limitation of 5A or less and an earth fault
clearance time of less than 1s. Alternatively a 3A external fuse rated to system voltage can be installed between the ECD’s pilot
terminal and the pilot conductor.
4.2.7
Stop Button - Optional
The stop button should be a normally closed switch installed in the pilot conductor. When opened, the ECD will detect an open
circuit pilot and trip on open circuit.
4.2.8
Start Button and Resistor - Optional
When remote
start mode is selected a 100Ω, 1%, 5W resistor must be installed in series with the pilot conductor. The start
button is then installed in parallel to this resistor. The start button should be a normally open switch.
Summary of Contents for ECD
Page 22: ...APPENDIX A DRAWINGS ...
Page 24: ...APPENDIX B APPROVALS ...