Atec Megger-DLRO200-115 - Manual

DLRO 200-115
Digital Low Resistance Ohmmeter
DescRiptiOn
The DLRO200-115 is designed to check and measure contact
resistance in high voltage circuit breakers, disconnecting switches
(isolators), busbar joints, or for any low resistance measurement.
The test set accurately measure resistances ranging from 0.1µΩ to
1Ω, at high currents.
This versatile instrument can provide test currents from
10 amps up to 200 amps, subject to the load resistance
and supply voltage. For those applications that demand a smooth
dc current, the DLRO200-115 has extra filtering on the output to
reduce mains frequency ripple and can drive 200 amps through a
total current loop resistance of
11 milliohms. The filtered output of the DLRO200-115 also
eliminates magnetic transients that could inductively trip a breaker’s
control (bus differential relay), if left in the test circuit.
The unique design allows the weight and size of the DLRO200-
115 to be kept to a minimum; the instrument weighs less than 32
lbs. (14.5 kg). This small size plus a water/dust ingress rating of
IP54 makes the test set equally at home in the workshop, on the
production floor or in the field.
As many as 300 sets of results may be stored in the test set’s
on-board memory for later download to a PC or may be sent
directly to a printer via the RS232 port. You may also add notes
to any stored result by using the on-board alphanumeric keypad,
thereby making later identification of results easier to determine.
As well as adding notes to stored results, the alphanumeric keypad
allows you to set the test current directly by keying in the value
required. The DLRO200-115 will check the continuity of the test
circuit, and will quickly ramp the test current up to the desired
level. The keyboard is also used to set upper and lower limits for
the result and to prevent the use of excessive currents by setting an
upper limit to the allowable test current.
The DLRO200-115 uses a four terminal measurement technique to
cancel the resistance of the test leads from the measurement.
The test set operates in one of three modes, which are simply
selected from the on-screen menu.
CONTINUOUS mode is provided for users who wish to monitor
a resistance over a period of time. Connect the test leads, select the
test current and press the TEST button. The DLRO200-115 will
pass a current continuously, and measure the load resistance at 2
second intervals, until the test button is pressed to stop the test or
the test circuit is interrupted.
In NORMAL mode you connect the leads, select the test current
and press the TEST button. The test current will ramp up to the
desired level, hold for 2 seconds and then ramp down. The whole
process takes approximately
10 seconds.
In AUTO mode select the desired current, connect the current leads
and press the TEST button. The TEST lamp will flash to show
that the DLRO200-115 is ready to carry out a test. As soon as
the potential leads are connected, a test will start. To repeat a test,
simply break contact with the voltage probes and remake contact.
Measuring individual joints in a busbar is a good example of the
convenience to be gained by using AUTO mode. The two current
leads are connected to the ends of the busbar. They will remain
n small and weighs less than 32 lbs (14.5kg)
n test currents from 10 A to 200 A d.c.
n Filtered direct current output eliminates
magnetic transients
n 0.1 µΩ best resolution
n On board memory for up to 300 test
results and notes
n Rs232 port to download stored results
or for real time output to a printer
n supplied complete with 16 ft. (5m)
test leads and download software
DLRO 200-115
Digital Low Resistance Ohmmeter