GE Power Quality Meter Series, Инструкция по эксплуатации

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A-18 PQM Power Quality Meter GE Power Management
A.1 PQM APPLICATION NOTES APPENDIX A
A
A.1.8 PULSE INPUT APPLICATION
APPLICATION NOTE PQMAN09: PULSE INPUT APPLICATION
The PQM has up to 4 Logical Switch Inputs that can be configured as Pulse Input Counters. Variables to con-
sider when using the PQM as a Pulse Input Counter are:
• PQM Switch Input A/B/C/D Function
• PQM Switch Input A/B/C/D Activation
• PQM Switch Input A/B/C/D Name
• PQM Pulse Input (Units)
• PQM Pulse Input A/B/C/D (Value)
• PQM Totalized Pulse Input
1. PQM Switch Input A/B/C/D Function: This parameter defines the functionality to be provided by the PQM
Switch Input. For use as a Pulse Input Counter, the PQM Switch Input to be used must be assigned as
either Pulse Input 1/2/3 or 4.
2. PQM Switch Input A/B/C/D Activation: This parameter is set to OPEN or CLOSED. The PQM will see the
operation of the Switch Input in the state as defined by this parameter.
3. PQM Switch Input A/B/C/D Name: This parameter 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.
4. PQM Pulse Input (Units): This parameter is the name given to the base units that the PQM Pulse Input(s)
will be counting. It is used as a label only and has no bearing on the operation of the Pulse Input.
5. PQM Pulse Input A/B/C/D Value: This is the value assigned to each counting operation as determined by
the Switch Input.
6. PQM Totalized Pulse Input: This parameter creates a summing register of the various Pulse Inputs config-
ured. It can be configured for any combination of the PQM Switch Inputs used as Pulse Inputs.
Application of the PQM 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 PQM Switch Inputs, the PQM Switch Inputs are not labeled with KYZ
markings as a dedicated pulse input device. However, the PQM can still be used as a pulse counter. The PQM
Switch Inputs require a signal from the PQM Switch Common terminal to be activated. The PQM 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 PQM is connected to the K terminal of the Pulse Initiator. The
PQM 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 PQM 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 clo-
sure for every 100kWh, the PQM Pulse Input (Value) must also be set to 100.
Various operating parameters with regard to the PQM Switch Inputs must be taken into account. The PQM
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 PQM is itself switched on and off at the times when the
PQM is reading the status of the Switch Inputs. Monitoring the input to one of the PQM Switch Inputs will reveal
a pulsed 24VDC waveform, not a constant signal. Standard wiring practice should be adhered to when making
connections to the PQM 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.