Models DC-1, -10, -20B DC Spark Testers
DC-1, -10, -20B Instruction Manual
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Page 23
Communication Modules
: The DC-B supports Modbus RTU via the RS-485 port. An optional
PCB may be added to the DC-B for easy communication to most PLCs. This PCB can be factory
installed or added later. Analog, DeviceNET, Ethernet/IP Profibus, Profinet, and Modbus TCP
protocols are all available options. Communication protocols can easily be changed at any time
with the purchase of an upgrade kit or a new plug-in module.
Voltage Watchdog
: Test voltage parameters can be set by users to ensure adequate test
voltages are always being used to test product. For example, if the spark tester should be
continuously testing at 4kV, users can set the system to alarm if the spark tester voltage were to
fall below 3kV or rise above 5kV. Preset upper and lower voltage limits may be set using the front
panel or remotely.
Redundant Voltage Monitoring
: In addition to standard voltage monitoring, the DC-B monitors
the voltage at the electrode to verify correct voltages are being maintained.
Four output relays
: One set of form C and three sets of form A relay contacts are located on the
back of the DC-B for easy connection to external alarms, lights, or machinery that will be
controlled by the spark tester. Relay functions can be selected from options including: High
Voltage ON indication, Fault Alarm, All Bare Wire Alarm (this includes both Direct metal contact
and gross bare wire conditions), and Voltage Watchdog.
Fault Typing
: Detecting the flow of current during spark testing has always been the standard in
spark testing. The DC-B revolutionizes the concept of fault detection by the use of DSP Based
Fault Typing. We can now differentiate 4 types of fault conditions: Pinhole, direct metal contact,
multi-pinhole, and gross bare wire.
Definitions of fault conditions
:
•
Pinhole-
A pinhole is defined as a short-duration fault where no direct metal contact
between the wire conductor and the electrode is made.
•
Multi-Pinhole-
A Multi-Pinhole is defined as two or more pinhole faults closely spaced. It
can also be a single fault of longer duration where no metal contact was made between
the wire conductor and the electrode.
•
Metal Contact
- Sometimes referred to as BARE WIRE. A Metal Contact fault is defined as
a defect or bare patch in the insulation that allows the electrode to come into momentary
direct contact with the wire conductor. In order for a fault to be typed as a metal contact,
the bead chain electrode must make physical contact with the conductor under test.
•
Gross Barewire-
Gross Barewire is defined as a fault where the wire conductor is exposed,
allowing metal contact to be made with the electrode for a period of time equal to two
and one half times the electrode length.
Backwards Compatible
: All that is needed for a customer to upgrade from the DC-A series to
the DC-B series is to unplug the power cord and the 9-pin green terminal strip from the back
panel on the DC-A and to plug it into the DC-B. The DC-B will function identically to the DC-A if
the user does not wish to use any of the additional features. The bolt patterns on the bottom of
the DC-B are the same as the DC-A for easy physical replacement.