RLE LD5200 V.2.3 - Manual (Page 115)

rletech.com LD5200 User Guide 115
A
P P E N D I X
C HAPTER 0
4-20
M
A O
UTPUT
T
ESTING
The LD5200’s 4-20mA output is loop powered and tested by the manufacturer. The
manufacturer guarantees its performance upon delivery. Should the 4-20mA output need to be
tested in the field, follow these steps. The following procedure is performed with the cable
connected, unless otherwise indicated.
1 Turn off all power to the LD5200
2 Remove the two position plug from TB1.
3 Remove any wires from the terminal and
install a 200Ohm resistor to TB1-2 (-).
Then apply +24V (TB7-2) to TB1-1 (+)
and ground (TB7-1) of the 24V supply to
the other side of the resistor.
4 Reinstall the plug on TB1.
5 Reapply power to the LD5200.
6 With the system on and no alarms present,
measure the DC voltage across the
resistor. A value of 0.8VDC or 1.0VDC
should register. This equates to 4mA 0r
5mA (depending on the LD5200’s
configuration), or normal operation.
7 Remove the SeaHawk Leak Detection Cable (SC) and wait for the unit to activate its cable
trouble alarm. Measure the DC voltage across the resistor. A value of approximately
3.8VDC or 4.0VDC should be measured. This equates to 19mA or 20mA (depending on the
LD5200’s configuration), or a fault alarm. Reconnect the SC cable.
8 Place water on the end of the SC cable. Measure the DC voltage across the resistor. The
value will be proportional to the length of cable measured by the LD5200 and scaled
according to the range setting. Dry the cable.
9 Place water on the start of the cable. Measure the DC voltage across the resistor. A
measurement of approximately 0.8VDC or 0.9VDC, or 4mA or 5mA (both depending on
the LD5200’s configuration), should be measured. This corresponds to a leak at zero
distance. Dry the cable.
Figure E.1 4-20mA Testing
TB1 TB7