GE PQMII, Инструкция по эксплуатации

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CHAPTER 7: APPLICATIONS
PQMII POWER QUALITY METER – INSTRUCTION MANUAL 7–23
7.8 Pulse Input Application
7.8.1 Description
The PQMII has up to 4 Logical Switch Inputs that can be configured as Pulse Input
Counters. Variables to consider when using the PQMII as a Pulse Input Counter are:
• PQMII Switch Input A(D) Function : Defines the functionality to be provided by the
PQMII Switch Input. For use as a Pulse Input Counter, the PQMII Switch Input to be
used must be assigned as either Pulse Input 1, 2, 3, or 4.
• PQMII Switch Input A(D) Activation : Set to Open or Closed. The PQMII will see the
operation of the Switch Input in the state as defined by this parameter.
• PQMII Switch Input A(D) Name : Defines the name given to each of the Switch
Inputs used. It is used as a label only and has no bearing on the operation of the
Switch Input.
• PQMII Pulse Input (Units) : Represents the name given to the base units that the
PQMII Pulse Input(s) will be counting. It is used as a label only and has no bearing
on the operation of the Pulse Input.
• PQMII Pulse Input 1(4) Value : This value is assigned to each counting operation as
determined by the Switch Input.
• PQMII Totalized Pulse Input : Creates a summing register of the various Pulse
Inputs configured. It can be configured for any combination of the PQMII Switch
Inputs used as Pulse Inputs.
7.8.2 PQMII Pulse Input(s) with a Pulse Initiator using KYZ Terminals
Typical end receivers require a contact closure between KY or KZ based upon the type of
receiver. Because of the multi-functional parameters of the PQMII Switch Inputs, the PQMII
Switch Inputs are not labeled with KYZ markings as a dedicated pulse input device.
However, the PQMII can still be used as a pulse counter. The PQMII Switch Inputs require a
signal from the PQMII Switch Common terminal to be activated. The PQMII configured as a
Pulse Counter can be used with Two-Wire Pulse Initiators. The Pulse Initiator must provide
a dry contact operation. The Switch Common terminal of the PQMII is connected to the K
terminal of the Pulse Initiator. The PQMII Switch Input assigned to count pulses can be
connected to the Y or the Z terminal of the Pulse Initiator, depending on the operation of
the Pulse Initiator, i.e. Open or Closed. The PQMII Pulse Input (value) must be assigned to
match the pulse value of the Pulse Initiator, i.e if the Pulse Initiator delivers a dry contact
closure for every 100kWh, the PQMII Pulse Input (value) must also be set to 100.
Various operating parameters must be taken into account. The PQMII Switch Inputs
require a minimum 100ms operation time to be detected. The duration of the contact
operation can be indefinite. The internal Switch Input circuit of the PQMII is itself switched
on and off at the times when the PQMII is reading the status of the Switch Inputs.
Monitoring the input to one of the PQMII Switch Inputs will reveal a pulsed 24VDC
waveform, not a constant signal. Standard wiring practice should be adhered to when
making connections to the PQMII Switch Inputs, i.e. avoiding long runs of cable along
current carrying conductors or any other source of EMI. An induced voltage on the Switch
Input can cause malfunction of the Switch Input.