Installation, Operation and Service Manual
LKAT Plus EMC
© 2018 DynAmp, LLC
Page 19
047331 A
Main PCB LED D6 is a RED / GREEN the Accuracy Diagnostics status LED. This LED
indicator and Main PCB relay CR2 contacts may be used to monitor the following conditions:
•
Measuring Head imbalance
•
Power supply failure
•
Measuring Head disconnected
•
Sensor electronics failure
•
Other circuit failures causing loss of measurement accuracy
Occurrence of one or more of the conditions above will change the state of the CR2 relay coil,
changing the state of the contacts and changing the LED indication from green to red. Refer
to the section “Troubleshooting an Accuracy Diagnostics Fault Indication” in this chapter for
more information about determining the cause and eliminating a fault condition.
Refer to section the “FAILSAFE”/ “NON-FAILSAFE” CONFIGURATION in this chapter for
more information about Alarm Relays.
5.4
LKAT PLUS METERING UNIT
Refer to drawings in the back of this manual.
Input power connects to the Power Supply pc board assembly. The power supply pc board
includes a non-replaceable slo-blo type fuse, in-rush and overcurrent protection, as well as
MOV overvoltage clamping. The power supply provides outputs of ±15Vdc and +5Vdc
required by the system electronics. These outputs connect to the Main pc board assembly
via a short wire harness.
Connections to the Measuring Head are made via the Main pc board assembly. The u-
chassis with power supply and Main pc board is mounted on a sub-panel inside NEMA-4X
enclosure. The enclosure cover must be securely closed and cable assemblies connected at
all times during normal operation.
5.5
LKAT PLUS MEASURING HEAD INTERCHANGEABILITY
DO NOT connect a LKAT²
Measuring Head to an LKAT
Plus Metering Unit – the LKAT²
Head
will not function properly, but not be damaged. LKAT Plus Measuring Heads of various sizes
will operate properly when connected to the LKAT Plus Metering Unit. However, the LKAT
Plus system is
factory calibrated as a system.
As a result, optimal measurement accuracy
is achieved when the Metering Unit is connected to the head it was calibrated with, and
installed on the size bus bar it was designed for.
5.6
TROUBLESHOOTING AN ACCURACY DIAGNOSTICS FAULT INDICATION
A problem may be detected when the LKAT Plus system is energized with A and B head
cables connected to the Metering Unit. When the Main PCB AD status LED D6 illuminates
RED and / or Main PCB CR2 status relay coil changes state, a possible fault condition has
been detected. This is true whether or not the Measuring Head is installed on the bus. The
following table is intended to help the user determine and eliminate the cause of the fault.
