An insulation alarm in a large solar installation does not identify the faulty string by itself. In Bender’s PV brochure, ISOMETER monitors the system’s insulation level, while ISOSCAN/EDS and suitable measuring current transformers help locate the relevant circuit.
Bender distributor in Türkiye · ADEO Teknik
Moisture, contamination and ageing can change insulation levels across large PV installations. Continuous insulation monitoring and fault location to identify the relevant circuit provide different information.
Two main insulation monitoring options for large-scale PV systems. Consider system leakage capacitance, measurement requirements and variant selection together.
Insulation monitoring with a graphical display in large photovoltaic IT systems, with an integrated locating current injector to support EDS insulation fault location.
Insulation monitoring in large-scale PV IT systems. Compare the technical data of the isoPV1685RTU-425 variant with the isoPV1685P-425 option on the same product page.
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Three PV inverters and the storage system connect to a common unearthed AC IT busbar. The battery connects to the AC side through a bidirectional PCS. isoPV1685DP or isoPV1685RTU in the AC panel monitors overall insulation condition. Select charging or discharging and mark the AC branches on which to create simultaneous faults. Inverters 1, 2 and 3 can be selected individually or together; PCS/storage and the outgoing AC branch can also be added. Set Riso and the AL1/AL2 thresholds in the measurement panel. The entered resistance updates the alarm state immediately. Play the scenario or proceed step by step: follow the insulation resistance drop, isoPV1685 prewarning and alarm, and identification of the selected faulty AC branches on separate DP + EDS channels. Scenario progress is retained when changing energy mode or faulty branch selection. The two IMDs are shown as alternatives in the same position.
Charging and discharging · AC panel ↔ PCS ↔ batteryInitial state: PV inverters and the storage PCS are connected to a common AC IT panel. Select the energy direction and one or more AC branches on which to create a fault; play the scenario or use “Next step”. Set Riso and the AL1/AL2 thresholds in the measurement panel; the alarm state updates accordingly. During playback, follow the resistance drop and threshold crossings. After the DP + EDS search, all selected faulty AC branches are shown with their own channel numbers. Riso measurement pauses during EDS operation; the last measured value is retained. RTU has no integrated locating current injector.
Riso is the equivalent insulation resistance to earth of the monitored AC IT system; it is not a measurement of a single branch. Initially, AL1 = 40 kΩ and AL2 = 10 kΩ are selected. Riso and both thresholds can be changed within the example range of 0.2–50 kΩ; AL1 cannot be lower than AL2. This range belongs to the simulation.
The thresholds and resistance values belong only to this educational example; they are not factory settings or application recommendations. Playback moves from the entered initial value to an illustrative fault value below AL2; if the lower limit prevents reaching a value below AL2, no EDS result is generated. Changing a value or threshold pauses the scenario and applies the new starting condition; energy direction and multiple branch selection are retained. Branch selection does not automatically change the overall system Riso; individual branch resistances are not calculated. When all branches are deselected, the general IMD alarm continues to depend on the entered Riso, while the EDS search and channel results close. The accelerated steps do not represent actual device response times. Multiple results are summarised together in this example; in a real system, locating current division between faulty branches and channel conditions can affect detection. EDS does not measure insulation resistance per branch. With RTU selected, the sequence ends at the general insulation alarm; EDS fault location in this example requires DP.
The IMD with graphical display in the AC panel monitors the insulation condition of the AC IT busbar. Its integrated locating current injector supports insulation fault location with EDS; insulation resistance measurement pauses temporarily during fault location.
DP technical details ↗Monitors the AC IT busbar from the same AC panel position as an alternative to DP. RTU has no integrated locating current injector; in this example, EDS fault location is available only when DP is selected.
RTU and P variants ↗The EDS in the AC panel evaluates the measuring current transformer on each PV inverter’s separate AC branch before it joins the common AC busbar. PV inverters 1, 2 and 3 are monitored on separate EDS channels; together with PCS/storage and the AC outgoing branch, all five AC branches can be selected simultaneously. EDS identifies each faulty branch through its own measuring current transformer and channel result. With charging or discharging selected, follow the Riso drop and the IMD’s AL1/AL2 alarm, followed by the DP + EDS search and the identification of the selected faulty AC branches on separate channels, all in the same view. Energy direction and insulation fault location are shown as separate layers. This does not represent DC string identification behind an inverter or battery cell fault location.
EDS440 and documentation ↗The storage branch joins the common panel through the bidirectional PCS’s AC connection. The battery is on the PCS’s DC side. During charging, energy flows from the AC panel to the PCS, which feeds the battery through AC/DC conversion. During discharging, energy flows from the battery to the PCS, which supplies the AC panel and outgoing AC branch through DC/AC conversion. PV generation is not shown during discharge. The measuring current transformer is shown on the AC side of the storage branch.
This is a conceptual educational example, not a wiring, tripping or safe operation diagram. Energy arrows continuing during alarms and fault location do not indicate automatic tripping or that a faulty system can operate safely. This view represents an unearthed AC IT system. The measuring point and IMD/EDS compatibility depend on inverter/PCS topology, galvanic connections, system capacitance and the selected variant. Architectures in the Bender PV brochure ↗ · AC and EDS connection example in the DP manual ↗ · Branch measuring current transformers in the EDS manual ↗ · Multiple-fault evaluation in the EDS manual ↗ · Insulation alarm and EDS measurement operation ↗
As Bender’s distributor in Türkiye, ADEO Teknik provides technical product information and quotation support for selecting IMDs, EDS devices and compatible measuring current transformers.
Contact us for solar product selection ↗ · Open-source licences ↗An insulation alarm in a large solar installation does not identify the faulty string by itself. In Bender’s PV brochure, ISOMETER monitors the system’s insulation level, while ISOSCAN/EDS and suitable measuring current transformers help locate the relevant circuit.
Related brochure section · PDF p. 10 ↗
System voltage, leakage capacitance and fault location requirements determine the product combination in large PV circuits.
After choosing a product family for the application, compare the model’s measurement scope, accessory compatibility and communication options on its detail page.
Explore related Bender models ↓The explanation, Bender’s relevant sector publication and official application page form the basis of this content. The image is presented in its original form from the source brochure.
Official Bender manufacturer publication
Open brochure PDF ↗Download PDF ↓Bender source document ↗
Original publication: Bender Industry Applications
Bender manufacturer publication · US / North American edition
Open brochure PDF ↗Download PDF ↓Bender source document ↗Product families fulfil different measurement and notification duties. The model’s full scope and required components are identified in the relevant technical source.
BENDER PRODUCT FAMILYApplication-specific ISOMETER® insulation monitoring devices for IT systems.
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BENDER PRODUCT FAMILYISOSCAN® / EDS products for identifying faulty branches in IT circuits.
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BENDER PRODUCT FAMILYProducts that combine measurement and alarm data from compatible devices.
Explore related products ↗You can request product information, manufacturer documentation and a supply quotation for this application.
Get product information for your application ↗System voltage, leakage capacitance and fault location requirements determine the product combination in large PV circuits.
Insulation monitoring device with graphic display and integrated locating current injector for large PV and battery energy storage systems.
Insulation monitoring devices for large photovoltaic IT systems up to DC 1500 V, with RTU communication or an integrated locating current injector depending on the variant.
Insulation monitoring in PV systems together with AGH420.
Portable insulation fault location in IT systems, with a separate residual current measurement function for TN/TT systems.
Explore all options in the relevant family. Assess model selection alongside system topology, voltage, measurement requirements and accessory compatibility.
Insulation monitoring · IMDCompare 30 products / series in this family ↗Insulation fault locationCompare 5 products / series in this family ↗As Bender’s distributor in Türkiye, ADEO Teknik provides technical product information and quotation support for model and accessory selection, manufacturer documentation and product supply.
Manufacturer document · English
Manufacturer document · English
Images and application content: official Bender sources. The relevant documents identify the exact model, variant and operating conditions.
Explore product group introductions and original manufacturer brochures with ADEO Teknik, Bender’s distributor in Türkiye.
Insulation monitoring · IMDIn an IT system, live conductors are not directly connected to earth. Behaviour during the first insulation fault is assessed alongside the system configuration, leakage capacitances and protection arrangement.Read the product group guide ↗
Insulation fault locationThe locating current injector, suitable measuring current transformers and EDS evaluator must be considered together.Read the product group guide ↗
Communication and central monitoringInterfaces such as BMS, BCOM and Modbus are selected according to the product's supported architecture. Do not assume every device supports every protocol.Read the product group guide ↗Contact your distributor in Türkiye for product selection, technical documents and quotations.
