A Lancaster one-line that stops at the inverter is short a utility device. The PPL DER management device, an open communications port, and a power tap for the enclosure all belong on the drawing. A second customer meter collar does not. Lancaster is PPL territory. Rule 12 applies to inverter-based DER applications received on or after January 3, 2026. A new application you file now is in that group. IEEE 1547-2018 and UL 1741 Supplement B are the inverter standards that go with it. The spec sheet in the package is the sheet that shows Supplement B for the model on the one-line, not a generic brochure for the product family.
What the Lancaster one-line has to show
The one-line still shows modules, inverter, point of connection, and the main or disconnect the design uses. Add a PPL-owned device on the inverter data port, the housing, the customer-provided communications port, and the power for the utility enclosure. A note that says utility equipment by others, with no port and no power, is not the drawing.
The housing is a sealed utility enclosure and/or a meter collar, matching the arrangement this application uses. Label it as utility equipment. Do not rename it as a customer monitoring cabinet. If a collar is used, one socket gets one collar. Multiple collars on one socket are not supported. The device is not a second customer meter.
- PPL-owned DER device on the inverter data port.
- Sealed utility enclosure and/or a single meter collar. No second collar on that socket.
- Open RS-485 or Ethernet port, provided by the customer.
- Enclosure power at 120 V or 277 V, with neutral and ground, from a source this service has.
- A pointer to the communication diagram that goes with the application.
Interconnection drawings for this utility are that one-line plus the diagram, not a permit sketch with a collar traced from another state. PPL interconnection is the package the device lives in. The municipal permit, if this job needs one, is a separate set. This article does not quote a Lancaster permit fee. Do not type one. Do make the inverter on the permit one-line match the inverter on the PPL one-line.
Call out the PPL DER management device
The device is PPL-owned. It sits on the inverter data port. Draw it there, with a callout a reviewer can find without reading the email. Ownership matters on the sheet because a customer-owned logger is not a substitute symbol. If sales handed you a one-line that already has a monitoring collar for the installer, that collar is not the utility device. Remove it if it would become a second collar on the socket. Keep the PPL device.
The REMSI sketch notes are the port and the power, drawn in the application rather than remembered from a meeting. The customer provides an open RS-485 or Ethernet port. The enclosure needs 120 V or 277 V, neutral, and ground. Show the voltage this service can actually supply. A service with no 277 V source does not get a 277 V note copied from a commercial sketch. Write the voltage on the one-line.
Multiple inverters are networked. Show which port is open and how the other inverters reach it. A sentence that says the inverters communicate is not a network. The communication diagram goes with the application, and the one-line names it so both sheets describe the same port.
Port, protocol, and the diagram
Two IP methods show up in the notes, and they do not mix. The diagram states which one this application uses. Writing both gives PPL a contradiction. Delete the method you are not submitting.
Modbus TCP
Modbus TCP uses a static IP. The address, the gateway, and the subnet are provided to PPL. Do not invent the octets. If you do not have them yet, say those three values will be provided to PPL, and leave fake numbers off the sheet.
IEEE 2030.5
IEEE 2030.5 uses DHCP. Do not also specify a static IP, a gateway, and a subnet on that path. DHCP and a hardcoded address are different instructions to the same port. If the application is IEEE 2030.5, the diagram says DHCP and stops. If someone pastes the Modbus note underneath out of habit, delete the paste.
What the diagram contains
The diagram shows the inverters, the open port, the PPL device on the data port, the IP method, and enclosure power at the voltage you selected, with neutral and ground. It does not show a second customer collar, and it does not show a curtailment percentage. Rule 12 does not give you one.
A Level 1 house still carries the device
Pennsylvania Chapter 75 is a different question from Rule 12, and both can apply to the same house. Level 1 is certified inverter equipment at 10 kW nameplate or less. A small house can be Level 1 and still need the DER device under Rule 12. Do not drop the device, the port, or the power tap because the nameplate is at or under 10 kW. The level describes that interconnection tier. Rule 12 describes the device on inverter-based applications received on or after January 3, 2026. Passing one check is not a waiver of the other.
Read Chapter 75 interconnection beside the device notes. Residential design still matches the PPL one-line on inverter, point of connection, and the device. Pennsylvania solar design does not drop the device because the house is Level 1. This article does not assign the other levels.
Upgrades, the outside date, and a device that arrives later
Existing systems without a device are not frozen forever, and they are not all due tomorrow. They must submit a new application when they upgrade, when they install a new inverter, or by January 3, 2041, whichever is earlier. Do not tell a customer who is already changing the inverter that they can sit until 2041.
A new inverter is a new application, not a redline on the old one alone. The new one-line carries the device, the open port, the network if there is more than one inverter, and the power tap. The communication diagram goes in with that application. Reusing the old diagram, which has neither a port nor a static-IP or DHCP note, imports the gap you are supposed to be closing.
If PPL has no compatible device, it may still approve the application and install a device later. Keep the data port, the open RS-485 or Ethernet port, the enclosure power at 120 V or 277 V with neutral and ground, and the sealed utility enclosure or the single meter collar. Later has to have a place to land. Do not fill the gap with a curtailment percent. Rule 12 does not publish one.
Permit design can carry the same one-line so the township set and the utility set do not diverge. Still no Lancaster fee, and still no second collar. Before the application goes in, confirm IEEE 1547-2018 and UL 1741 Supplement B on the inverter, the device on the data port, one collar at most, one IP method, and a power tap this service can actually feed. If any of those is missing, the file is still a draft, including on a Level 1 house and including when PPL may set the device later.