PMC-340 FAQ’s
PMC-340 NMI Approved Digital Three-Phase Energy Meter
Designed for Reliability – Manufactured to Last
High-accuracy DIN-rail mounted energy meter with IEC 62053-21 / 22 compliance, Modbus RTU communication, optional data logging, and multifunction true RMS measurements for industrial and commercial energy management.
PMC-340 FAQs
What is the difference between the PMC-340-A and PMC-340-B energy meters?
The main difference between the models is the PMC-340-B provides extra functionality that the PMC-340-A does not have;
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2MB memory for Data Recording
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16 SOE event log
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3 Digital Inputs for external status monitoring
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PMC-340-B can be certified NMI compliant
- PMC-340A-A – Direct connect/Whole current
- PMC-340A-B – CT connect
- PMC-340B-A – Direct connect/Whole current
- PMC-340B-B – CT connect
The Direct connect/Whole current PMC-340 meters can take up to 100Amps directly into the meter, whereas the CT connect PMC-340 requires current transformers.
CT example 500/5A; Each phase of the 3 phase circuit are fed through the current transformers primary source side of the CT heading to the load (as per example up to 500A). Wires attached to the secondary side of the CT generates a ratio of that primary current source (as per example 5A). The calculations will be based around the input source (amps) into the meter.
I need to monitor 3x single phase circuits for revenue purposes. Can I connect the PMC-340 meter to monitor the phases separately for this purpose?
In theory this is possible, as the meter does give you the separate phase data, however, the meter was not tested for this type of use and is not NMI compliant working in this manner. For revenue purposes we recommend 3x separate meters for this arrangement; perhaps 3x PMC-220/230s.
Can you help specify the size of HRC fuses required for the PMC-340 meters?
The direct connect/whole current PMC-340-BA meter is rated at 100Amps and therefore should be installed with an 80Amp HRC fuse.
Can you tell me what the watt loss is for your CET PMC340 meter series is?
These meters draw about 20mA to power themselves, which at 240VAC is <5W. The thermal losses would be equivalent to 10cm of the max supply cable size (25mm2) at the current flow being considered at ambient temperature.
What is the short-time overcurrent rating of the PMC340 models?
Specifications for maximum withstand current rating; test reports for the PMC-340 direct connect/whole current models state that they meet IEC 62053-21: 2003 requirement for short-time overcurrent without damage, which is 30 x Imax for 10ms.
30 x Imax for PMC-340 Direct Input Model = 3,000A.
At what energy count does the CET meters rollover occur?
PMC-340 energy register maximum value is 1,000,000,000, so the PMC-340-A energy roll over value is 100,000,000.0 kxh and PMC-340-B energy roll over value is 10,000,000.00 kxh.
Can the PMC-340 pulse output rate be adjusted?
Yes, the PMC-340 pulse output can be adjusted. Please see the manual on energy pulse output for relevant information. Please select manual for relevant meter model from the website: https://lpaenergygroup.com/smart-meters/.
Can you supply a CT wiring diagram for the PMC-340-BB please?
Wiring diagrams can be found in the manual. Please note you will also have to confirm wiring in the meter setup configuration. Please select manual for relevant meter model from the website: https://lpaenergygroup.com/smart-meters/.
What CT’s are recommended for use with tenant/revenue billing meters i.e. the PMC-340-BB meter?
For NMI compliant meters, LPA recommends to use CT’s with the best accuracy class possible to meet the project requirements. For example; the PMC-340-BB CT input 5A/6A, <0.5VA/phase Burden, accuracy class 0.5S.
Will I still have power if the meter fails?
The power would continue to flow as normal, however, there would be no meter readings in this case.