How much does an arc flash study cost? VB prices the engineering per bus, shows the options line by line, and the calculator gives you your band now.

For a US site with current drawings, VB's indicative bands put the engineering at about $4,500 for a site under 25 buses, $9,000 to $28,000 for 26 to 100 buses, $28,000 to $75,000 for 101 to 300 buses, and $75,000 upward for a campus above 300 buses. Field data collection by VB, labels printed and installed, and boundary marking are separate lines, typically adding 30 to 60 percent when all three are chosen. The calculator on this page returns your band with the options you pick; the quoted figure comes with the scope in two business days.

There is no useful average, because a 20-bus warehouse and a 400-bus data center campus are both arc flash studies. The useful number is the price per bus: VB's modeled basis is roughly $140 per low-voltage bus, $260 per medium-voltage bus and $400 per bus above 15 kV, for the engineering, with a minimum project fee for small sites, plus about $45 per bus for VB field data collection, $25 per label printed and installed, and $60 per bus for boundary marking if you want them. Multiply by your bus count by class and you have a budget figure before anyone visits.

Because the work is at the equipment, not across the floor. Every bus (a switchboard section, an MCC, a panel, a disconnect) is a cubicle to open, a device to record, a node to model and a label to install. A 100,000 square foot warehouse with twelve panels costs less than a 10,000 square foot plant with eighty. VB quotes per bus by voltage class so the number can be checked against your one-line.

Five things, in order of effect: missing one-line drawings (VB draws them, adding about 30 percent to the field phase), outdated drawings (about 12 percent for reconciliation), buses above 600 V (more devices, relay settings, utility coordination), DC buses (UPS strings and battery cabinets by the NFPA 70E Annex D.5 method, priced as their own line), and multiple sites (travel and separate reports). Hard-to-access equipment and night or outage windows add field time and are priced from the walkdown plan.

Current, verified one-lines; the utility fault current letter in hand; the plant's electrical team filling VB's pre-visit data sheet (settings, nameplates, cable schedules); unescorted access to the switchgear rooms on the agreed dates; and combining the study with a coordination review or a five-year reassessment already due. VB prices the data-sheet reduction as its own line so you can see what your team's hour is worth.

The engineering price includes the label content for every bus to NFPA 70E 130.5(H) as a print-ready file. Printing and installing the labels, collecting the field data on site, and marking the arc flash boundary on the floor are three separate option lines, priced per bus and per label on the quote, so you choose what VB does and what your own team does. Many plants collect their own data on VB's pre-visit data sheet and have VB print and install the labels, because that is where the study date and the figures most often go wrong.

Below about 25 buses a per-bus rate does not cover the fixed work: the utility request, the walkdown day, the model setup, the review and the PE stamp are the same whether there are eight buses or thirty. VB applies a minimum project fee for small sites, stated on the quote, and the calculator shows when it applies.

It looks cheaper and usually covers less. A manufacturer's study covers the gear it supplied, at factory settings, against the fault current the specification assumed, and it is seldom stamped by a PE licensed in the facility's state. The rest of the plant, the as-installed settings and the utility contribution on the day of energization are not in it. VB reviews bundled studies free and prices only the gap.

Lower than the first study when VB holds the model. NFPA 70E 130.5(G) requires review at intervals not exceeding five years; with the previous model in ETAP or SKM and the field data in ElecTwin, the reassessment is a delta walkdown of what changed, re-run scenarios and new labels. VB quotes it per changed bus plus a verification walkdown, which is typically well under half the first-study figure for the same site.

A VB practice engineer reads your bus counts, drawings state and DC answer, checks them against your one-line if you attach it, and replies within two business days with the scope in four tasks, the quoted figure per line, the duration by phase and the name and license state of the signing engineer. The quote is firm for 60 days. No call unless you ask for one.