Predictika · Commercial rooftop solar PV with EV charging: string design, roof, grid connection and terms

An AI sales agent's solar and EV charging quote, checked before it goes out

An AI sales agent prepares a quote for a commercial rooftop solar and EV charging kit for a fictional customer. Before it goes out, the agent sends it to Predictika’s validator, which checks it against the electrical design, roof, grid connection and pricing rules, compares the net total the agent states with the one it computes, and returns a verdict with every reason.

Scope: commercial rooftop solar PV plus EV charging kit quotes (modules, inverters, mounting, chargers): string design, roof and grid checks, pricing and terms. See everything this validator covers

This validator models quotes for a commercial rooftop solar PV plus EV charging project kit of the kind a distributor such as Rexel supplies. It handles any combination of the three modeled modules, three inverters, four chargers, four mounting systems, roof types and grid connections, not just the scenarios shown below.

  • PV array and inverter sizing — Module and inverter pairing checked against string voltage windows, string inputs and the DC/AC ratio (131 to 150 percent needs design approval).
  • Mounting and roof — Ballast, anchored, rail or carport-structure mounting checked against the roof type, spare roof load and roof area; carport structures need an engineering sign-off.
  • EV charging and grid connection — AC and DC chargers checked against grid headroom (with optional dynamic load management), the 100 kW grid operator approval threshold, inverter power against the connection, and charger cable runs.
  • Lead time, pricing and the stated total — Lead time across the catalogs, distributor tier and project volume discounts, extra discount authority, and a check that the net total the agent states matches the validator total.

It does not cover other product categories (standalone electrical distribution gear, lighting, industrial automation), products outside the modeled catalogs, or real Rexel prices or terms.

The AI sales agentBuilds the quote from the conversation and says it is ready.
Predictika validatorChecks the quote against the product and contract rules and returns every finding it has.

7 scenarios in 3 groups · each group runs from the agent’s first attempt to the outcome · click one to switch

What the agent proposes

The AI sales agent says

Illustrative agent statement. The validator receives the structured request below.

Proposing agent: AI sales agent (scripted)

Before sending, the agent must call Recorded run

Predictika validator


      

        
        
        
      

      
Waiting for the call.

      
    

  

  
    

    
Where rules-based CPQ gets it wrong
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Our assessment of what a typical rules-based CPQ (product rules, price rules and validation rules, as in Salesforce CPQ or Revenue Cloud) does with the same cases. It is a judgment about effort and reliability, not a claim that nothing can be built.

    
What the validator catchesTypical rules-based CPQPredictika
String voltage window and inverter inputsOnly with workarounds
The string voltage depends on the module count per string, a per-module voltage at cold and hot temperatures and the chosen inverter limits; chaining those into several comparisons usually takes a stack of validation rules kept in step by hand.		The string voltages are computed once from the module and inverter data and compared with each inverter limit on every call.
DC/AC ratio from the configured quantitiesOnly with workarounds
The ratio comes from module count, module wattage, inverter count and inverter size, with a band that blocks and a band that needs approval.		The ratio is computed from the choices and both bands are checked together.
Roof area and load that depend on the mountingOnly with care
Area and load rules change with the mounting choice, and each mounting has its own roof type; each rule is simple, keeping them complete is the work.		Roof type, load and area are checked together with the mounting.
EV load against grid headroom with load managementOnly with workarounds
The load that counts changes when dynamic load management is on, and the headroom depends on two other inputs.		Both loads and the headroom are computed and compared on every call.
Lead time across three catalogsOnly with care
Lead time is the maximum across the module, inverter and charger catalogs, with a short expedite band that needs approval.		Lead time is computed from the three catalogs and compared with the time available, with the approval band.
Tier, volume and extra discounts with authority limitsOnly with care
Three discounts that add up, with a limit that depends on the list value, need separate rules and an approval step.		All discounts and thresholds are evaluated together and returned with the reason.
The net total the agent statesOnly with workarounds
Comparing a stated total with a computed one means a separate rule per quote layout, and price rules rarely run on stated figures.		The stated net total is a field in the request and is checked against the computed total.
Every problem returned in one answerOnly with workarounds
Rules tend to fire as the quote is saved, so a rep often fixes one error and meets the next.		All findings come back together, whatever order the choices arrived in.

  

  

    
What this validator catches
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Every rule is checked on every call, in whatever order the choices arrive, and one problem never hides another. Blocking findings stop the quote; approval findings need a person to sign off; everything else is computed.

    
RuleEffectWhat it checks
1blockString open-circuit voltage at the coldest temperature must not exceed the inverter maximum DC voltage
2blockString voltage at hot cell temperature must reach the inverter lower MPP limit
3blockStrings must fit the inverter string inputs (inverters times inputs per inverter)
4block, then approvalDC/AC ratio below 80 or above 150 percent is blocked; 131 to 150 percent needs design approval
5blockMounting must suit the roof type: ballast or anchored on flat, rail on pitched, carport structure on carport
6blockBallast mounting needs at least 25 kg/m2 of spare roof load
7blockRoof area needed (modules x module area x row-spacing factor) must fit the roof
8needs approvalA carport structure needs a structural engineering sign-off
9blockEV charger load must fit the grid headroom (connection minus existing peak); with dynamic load management only 40 percent is counted
10needs approvalInstalled EV power above 100 kW needs grid operator approval
11blockInverter AC power must not exceed the grid connection
12blockThe supply cable run for each charger is limited by charger class (voltage drop)
13approval, then blockLead time is the longest of the module, inverter and charger lead times; up to 2 weeks short needs an expedite approval, more is blocked
14computedPV kit list = modules x (module + mounting + cabling) + inverters; EV kit list = chargers x (charger + cable run x cable price)
15computedDistributor tier discount (Installer 0, Silver 4, Gold 7 percent) and project volume discount (3 percent from EUR 100,000, 5 percent from EUR 250,000 list)
16approval, then blockExtra discount: up to 2 percent for a rep, approvable up to 6 percent (10 percent on lists of EUR 250,000 or more), blocked beyond that
17blockThe net total the agent states must match the validator net total within EUR 1

  

  

    
Scenarios and results
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The recorded result of the validator for each scenario on this page: the request the AI agent sent, the verdict, and every finding, in the order they appear above.

    
1. PV string design: Strings of 24 modules

    
The agent's request. A commercial rooftop kit for a flat warehouse roof: 144 Trina Vertex S+ 430 W modules in 6 strings of 24 on one SMA Sunny Tripower CORE1 50 inverter, ballast mounting, plus six 11 kW AC wallboxes with 40 m of supply cable each, for a Silver-tier installer. Net total EUR 34,982.40. Ready to send.

    
Verdict: Blocked.

    
    
      
  • String voltage above the inverter limit. 24 modules per string reach 1008 V at the coldest site temperature, above the 1000 V limit of the SMA Sunny Tripower CORE1 50.
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2. PV string design: Strings of 18 modules

    
The agent's request. A commercial rooftop kit for a flat warehouse roof: 144 Trina Vertex S+ 430 W modules in 8 strings of 18 on one SMA Sunny Tripower CORE1 50 inverter, ballast mounting, plus six 11 kW AC wallboxes with 40 m of supply cable each, for a Silver-tier installer. Net total EUR 34,982.40. Ready to send.

    
Verdict: Allowed.

    
3. EV charging and grid: Four twin chargers

    
The agent's request. A rooftop kit for a flat retail-park roof: 144 Trina Vertex S+ 430 W modules in 8 strings of 18 on one SMA Sunny Tripower CORE1 50 inverter, ballast mounting, plus four 22 kW AC twin chargers with 40 m of supply cable each, for a Silver-tier installer. Net total EUR 37,632.00. Ready to send.

    
Verdict: Blocked.

    
    
      
  • EV charging exceeds the grid headroom. The EV chargers add 88 kW against 80 kW of grid headroom (200 kVA connection, 120 kW existing peak).
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4. EV charging and grid: With load management

    
The agent's request. A rooftop kit for a flat retail-park roof: 144 Trina Vertex S+ 430 W modules in 8 strings of 18 on one SMA Sunny Tripower CORE1 50 inverter, ballast mounting, plus four 22 kW AC twin chargers with 40 m of supply cable each, with dynamic load management, for a Silver-tier installer. Net total EUR 37,632.00. Ready to send.

    
Verdict: Allowed.

    
5. The total the agent states: Stated total too low

    
The agent's request. A rooftop kit for a flat garden-centre roof: 120 JA Solar DeepBlue 4.0 455 W modules in 6 strings of 20 on two SMA Sunny Tripower X 25 inverters, anchored mounting, plus four 22 kW AC twin chargers with 45 m of supply cable each, for an Installer-tier customer. Net total EUR 37,772.00. Ready to send.

    
Verdict: Blocked.

    
    
      
  • Stated net total differs from the validator total. The net total the agent states (EUR 37772.0) differs from the net total the validator computes (EUR 39760.0).
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6. The total the agent states: Stated total corrected

    
The agent's request. A rooftop kit for a flat garden-centre roof: 120 JA Solar DeepBlue 4.0 455 W modules in 6 strings of 20 on two SMA Sunny Tripower X 25 inverters, anchored mounting, plus four 22 kW AC twin chargers with 45 m of supply cable each, for an Installer-tier customer. Net total EUR 39,760.00. Ready to send.

    
Verdict: Allowed.

    
7. Approvals: Solar carport with 150 kW charger

    
The agent's request. A solar carport kit: 200 LONGi Hi-MO 7 580 W bifacial modules in 10 strings of 20 on one Huawei SUN2000-100KTL-M2 inverter, carport structure, plus one 150 kW DC high-power charger with a 30 m supply cable, for a Silver-tier installer. Net total EUR 143,499.00. Ready to send.

    
Verdict: Needs approval.

    
    
      
  • Carport structure needs an engineering sign-off. A carport structure for 200 modules needs a structural engineering sign-off.
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  • Grid operator approval needed. 150 kW of installed EV charging is above 100 kW and needs grid operator approval.
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Narration transcript
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The text of the narrated walkthrough, step by step.

    
    
      
  1. Welcome to a demo of Predictika's Validator. An AI sales agent prepares a quote for a commercial rooftop solar and EV charging kit for a fictional customer. Before it goes out, the agent sends it to Predictika’s validator, which checks it against the electrical design, roof, grid connection and pricing rules, compares the net total the agent states with the one it computes, and returns a verdict with every reason.
    2. 
      
  2. I will start with the first request by the agent.
    3. 
      
  3. The agent says. A commercial rooftop kit for a flat warehouse roof: 144 Trina Vertex S+ 430 W modules in 6 strings of 24 on one SMA Sunny Tripower CORE1 50 inverter. Net total EUR 34,982.40. The rest of the request is on screen.
    4. 
      
  4. Before it goes out, the agent calls the validator.
    5. 
      
  5. Blocked, with one finding, all in one answer. 24 modules per string reach 1008 V at the coldest site temperature, above the 1000 V limit of the SMA Sunny Tripower CORE1 50.
    6. 
      
  6. The validator returned one blocking finding in one answer. A check that reads one field at a time would pass most of this; it shows only when the choices in the quote are checked against each other.
    7. 
      
  7. What this shows: for string voltage window and inverter inputs, a rules-based CPQ can do this only with workarounds.
    8. 
      
  8. Now the agent resubmits.
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  9. The corrected request. It changes the strings to 8 and the Mod Per String to 18.
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  10. It calls the validator again.
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  11. This time the validator clears it.
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  12. The validator also returns the line-item quote. It starts with Trina Vertex S+ 430 W module and Ballast mounting system; the other five lines are on screen.
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  13. The earlier finding is cleared, and the validator's total, EUR 34,982.40, matches the quote.
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  14. One problem caught in one call, fixed in one pass, and a clean quote. That is the value of Predictika's validator: catching mistakes before they reach the customer.
    15.