DAB Esybox Max Duplex Variable Speed Booster System, Dock, I/O, Tank

A complete two-pump commercial pressurisation system built on the E.SYBOX MAX platform. The units associate wirelessly — no external controller — and stage sequentially: one pump modulates at light demand, additional pumps join as demand climbs, for up to 153 GPM. Lead priority rotates on runtime so wear is shared, and any unit can be set as reserve for fault redundancy. Each E.SYBOX MAX keeps its own inverter, sensors and motor control; the Esydock Max is the shared hydraulic base. The Esy I/O module adds float, pressure-switch, remote-alarm and building-management connections, and a 6-gallon tank reduces cycling.

The group is governed by four parameters: N pumps detected, NA allowed to participate, NC allowed to run at once, and IC per-pump auto-or-reserve. Configure all pumps active for full flow, N+1 with one reserve for redundancy, or cap simultaneous operation while rotating duty. Anti-stagnation rotates every pump into service at least once per 23 hours. All pumps must run matching firmware and maximum-speed settings.

Source: DAB Esybox Max US Technical Sheet 50250413, 2026; system items as supplied by Watermain Supply.

Published DAB data for the two-pump system, by model. Figures are the pressure the system adds at each total flow. Curve tolerance per ISO 9906; based on water at ~1 mm²/s and ~1000 kg/m³.

Models

M = single-phase 208-240V; T = three-phase 380-480V. Max pressure added is DAB’s Delta P max per pump; the set point range is 15-174 psi. Values are per pump; system flow scales with pump count. Source: DAB Esybox Max US Technical Sheet 50250413, electrical data.

Pressure added in PSI, two pumps running, by system flow

Converted from the head DAB prints in feet in its two-pump table (PSI = ft ÷ 2.31), at the flows DAB tabulates for all three models, rounded to the whole GPM. The first tabulated flow, 42 GPM, is left out: it equals shut-off on every model (DAB’s pressure cap). The full table is in the Technical Leaflet on the Data Sheet tab. Bold = the last point on that model’s curve, its max flow; — = beyond it.

Drawing from a tank, cistern or well — nothing arrives with pressure, so what the pumps add is what you get. Read the table straight through: a 60/120 pair set to 70 psi delivers about 80 GPM.

Fed by a city main — the pumps add on top of what already arrives, up to 83, 97 or 136 psi depending on model, and the controller holds a set point of up to 174 psi in total. A 60/120 pair on a 40 psi main set to 70 psi only has to add 30 — and at 30 psi of added pressure its table gives roughly 127 GPM instead of the 80 GPM a tank would. Incoming pressure turns into extra flow at the same set point.

Read at the flow the group delivers. More pumps hold more pressure at any working flow because each carries a share of the flow and sits higher on its own curve; only the shut-off head at zero flow is fixed by the model.

Best operating range: 45/120: 38 to 66 GPM · 60/120 and 85/120: 48 to 80 GPM, derived from the single-pump range times the number of pumps.

Zero flow is the shut-off point — a ceiling, not a working point. Feet of head = PSI × 2.31. These figures are at full speed; the drives hold lower pressures by running the pumps slower. Source: DAB Esybox Max US Technical Sheet 50250413, 2026.

This is a custom-assembled commercial system and ships without a single manufacturer EAN. All pumps must run matching firmware and maximum-speed settings. Confirm the duty point against the system curve; for engineering-led sizing and a factory submittal, contact us before ordering.

Parts in contact with the liquid, per the manufacturer technical sheet.

All pumps connect to H2D, DAB’s official app, which replaces DConnect.

• Free: guided setup, live status and basic parameters, error overview and alarm alerts.
• Free: share an installation with up to 2 users (10 with Premium).
• Premium subscription: change settings and manage the pumps from anywhere, full alarm and usage history, data-log analysis and PDF reports.
• H2D Desktop opens the same installations on a tablet or computer.