Entron EN1000 series

Page 150 • 700120S • ENTRON Controls, LLC.
measuring signal around the ground loop circuit. This circuit comprises the main equipment grounding conductor,
a section of the equipment casing and a pilot conductor return path. When the Weldsafe 5000 detects a loop
resistance in excess of 1 , it will activate the output alarm relay (K2). The response time will vary depending upon
the actual loop resistance value. A time delay of up to 2 S can occur for values less than 2 . The Weldsafe will
react in < 30 mS for values approaching “open circuit” (see Table 1).
• Earth Voltage Build-up
The Weldsafe 5000 can also detect large ground fault currents that may cause unsafe voltage build-up on the
ground path. If the unit senses a voltage >30 V ac on the ground path, it will immediately react to this condition.
• Optional End-of-Line Resistor (EOL)
The Weldsafe 5000 ground checking operation has an additional protection feature. The unit can detect crush or
parallel faults. This situation occurs when the cable ground wire becomes unintentionally connected to the equipment
pilot wire. To sense this fault, a grounding resistor is connected at the end of the pilot wire from terminal 29. In this
configuration, the Weldsafe 5000 will alarm if the ground wire ever comes into contact with the equipment pilot
wire. This grounding resistor must have a value of 49.9 ohms with a high tolerance of +/- 0.1% to ensure proper
function of the Weldsafe 5000. Circuit Savers can supply this resistor on request. Please note: this end-of-line
(EOL) will not affect the operation of the earth voltage build-up function.
Weldsafe 5000 Technical Information
Mounting and Wiring
The Weldsafe 5000 can be either DIN rail mounted (35mm)
or screw-mounted by the 2 holes at the corners of the device.
Terminals are clearly marked for connection.
Input Power Supply
The Weldsafe 5000 requires an auxiliary power supply of
either 24 V ac or 120 V ac, 50-60 Hz. Customer must specify.
Trip/Alarm Output Relays
Two sets of changeover trip/alarm contacts (one for ground
fault, one for ground check) are provided rated at 250 V, 5
A. These two relays can be set for tripping or remote
indication. They can be configured for either failsafe or active
operation, manual or auto reset. Factory settings are
Failsafe and Auto Reset. To adjust relay for Failsafe/Active
operation for either ground fault or ground check, open front cover. There is a small blue button in the left and right
lower areas. The switch on the left changes the ground fault, the one on the right changes the ground check. For
Hand reset close contacts between 18-19, open for Auto.
LEDs
In addition to the trip relays there are six LED indicators on the front cover. The green LED indicates POWER ON.
There are two red LEDs for the ground fault function:
• “GF” indicates leakage in excess of preset trip level
• “C.T.” indicates C.T. connection broken
There are three LEDs indicating different conditions on the ground check function:
•“1” indicates ground loop resistance in excess of 1 ohm
• “Link” indicates ground wire connected to pilot wire
• “>V” indicates voltage build-up in excess of 30 V ac
Test/Reset
The test facilities on the Weldsafe 5000 may be operated locally or remotely. They test both the ground fault
sensing and the ground checking circuits. The test button, S1 is used to simulate a ground fault condition internally
as a means of testing the relay function. An external test button can also be used to perform the same function
test.
CT600 Current Transformers
CT600/25/WKE 1” internal diameter
CT600/60/WKE 2 1/3” internal diameter
CT600/95/WKE 3 3/4” internal diameter
CT600/130/WKE 5 1/8” internal diameter
CT/600/60/2 2 1/3" internal diameter for high current applications, 6" metal insert
Weldsafe 5000 Data Sheet • Circuit Savers • phone: (972) 370-0664 • www.circuitsavers.com • March 10, 2006
GF>10mA
Fault
C.T.
Leakage
Current
Ground
Continuity
>1Ω
<V
Test Reset
ON
Weldsafe 5000
Ground Fault Relay
Ground Continuity Relay
1
23
45
67
8
9 101112 131415
16 17 18 19 20
21 22
23
24 25 2726 28 29
30
Link
Weldsafe 5000 combination ground fault sensing and ground checking relay
APPENDIX D WELDSAFE 5000 (cont.)