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COLD ROOM & RIPENING CONTROL / GIZMO

Holds the cold room.
Runs the ripening.
Records every batch.

GIZMO RAC is a wall-mounted controller that runs cold rooms and ripening chambers by itself, keeps running without internet, and keeps a tamper-evident record of every ripening batch.

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Cold storage Ripening

Pilot program 2026 · Hardware revision A · Specifications may change.

RAC web app overview: two cold rooms and two ripening chambers with live air and pulp temperatures, humidity, CO2, ethylene estimate and relay states.
RAC / OVERVIEW Web app · demo site, simulated data
INTERACTIVE CHAMBER SIMULATION

Seven checks before every dose. Try to break one.

This panel applies the controller's dosing rules to a 50 m³ Alphonso batch in its Gassing stage. Open the door, trip the gas-leak input, load hot fruit or cut the internet, and watch what the controller does, and what it refuses to do.

RIPENING 1 / ALPHONSO · GASSING DOSE 3 DUE · ALL CHECKS PASS
Stage 2 of 5 · Gassing · 12 h 00 min of 24 h Simulation · time compressed
Pulp 121.4°C
Pulp 221.8°C
Air21.0°C
RH89%
CO₂1,950ppm
Ethylene est.0ppm
Ethylene valveCLOSED
Exhaust fanOFF
CoolingOFF
HumidifierOFF
Dose 3 · 5.0 L for 100 ppm est. in 50 m³READY
Software pulse cap 90 s · hardware timer cuts gas at about 2 min0 s / 75 s
R1 ALPHONSO GASSING
PULP 21.4/21.8 A21.0
RH 89% CO2 1950ppm
DOSE 3 DUE ALL OK

Panel display · 20 × 4

Dosing interlocks · checked before every dose
  1. 01
    All pulp probes at or below 24.0 °CMax 21.8 °C
    PASS
  2. 02
    No gas leakLeak input normal
    PASS
  3. 03
    Door closedClosed
    PASS
  4. 04
    CO₂ below 5,000 ppm1,950 ppm
    PASS
  5. 05
    6 h since the last dose start6 h 00 min since dose 2 started
    PASS
  6. 06
    Ethylene est. + dose stays within 100 ppmest. 0 + 100 = 100 ppm
    PASS
  7. 07
    Daily gas budget left20.0 of 30.0 L left · dose 5.0 L
    PASS

Dose 3 is due. The controller checks all seven interlocks before it opens the valve.

TWO MODES, ONE CONTROLLER

Cold storage or ripening. Same box, same discipline.

Each chamber runs in one of two modes. The controller switches every machine through a contactor, and checks its rules every 500 ms.

Cold storage

Holds temperature, humidity and VOC.

Compressor, dehumidifier or humidifier, heater and exhaust fan, each switched through its contactor.

  • One sensor drives one machine. A temperature change never touches the humidity machine.
  • ON and OFF thresholds per channel with a minimum deadband, so machines do not flicker on and off.
  • Compressor protection: the 180 s minimum OFF time is never skipped; machines restart 3 s apart after power returns.
  • Schedules: up to 8 time windows per channel, overnight windows allowed.
  • Manual override from the app or the panel always expires on its own: 30 min by default, 8 h at most.
  • Sensor fault: that channel goes to its fault action and raises an alarm; the others keep running.
  • Critical limits force a safe state, for example VOC at 2,000 ppm forces the exhaust ON.
  • Example set points: compressor ON at 4.5 °C, OFF at 3.0 °C. Mango holding room 12–13 °C.
Ripening

Runs a recipe, stage by stage.

Warm-up → Gassing → Vent → Hold → Cool hold, run by the controller from a versioned recipe.

  • Ethylene never above 100 ppm, designed around FSSAI's 100 ppm ethylene limit.
  • Dosed by valve time × flow rate. The ppm shown is an estimate and is labelled "est.": a 50 m³ chamber at 100 ppm needs 5.0 L.
  • Re-dose no sooner than 6 h after the previous dose start. A daily gas budget caps total gas.
  • CO₂ venting: exhaust ON at 5,000 ppm; the vent completes below 2,000 ppm after at least 10 min of exhaust.
  • Probes: up to 2 pulp probes per chamber, plus air (and optional supply and return air) probes.
  • Batch record: lot number, variety and weight (0.1–50 t) for every batch.
  • Chilling guard: cooling is blocked if pulp falls to 10 °C or below.

Every 500 ms, in this fixed order

  1. Admin deactivation
  2. Critical limit
  3. Manual override
  4. Schedule
  5. Sensor fault
  6. Normal thresholds
RIPENING CYCLE

A recipe, not a guess.

Ripening runs as five stages from a versioned recipe. Pick a recipe to see its stages and one batch drawn to scale over the cycle hours.

Mango — Alphonso standard

Version 3 · ethylene up to 100 ppm est.

  1. 01 / Warm-up

    Warm-up

    10 h
    • Pulp 20–22 °C
    • RH 85–92 %
  2. 02 / Gassing

    Gassing

    24 h
    • Ethylene up to 100 ppm est.
    • Pulp 20–22 °C
    • RH 87–95 %
    • Re-dose ≥ 6 h after the previous dose start
  3. 03 / Vent

    Vent

    until CO₂ < 2,000 ppm
    • Exhaust at least 10 min
  4. 04 / Hold

    Hold

    48 h
    • Pulp 19–21 °C
  5. 05 / Cool hold

    Cool hold

    until the batch is closed
    • Air 12–13 °C
    • RH 85–90 %
Pulp temperatureRecipe pulp bandEthylene est.CO₂

Scroll the chart sideways →

Mango — Alphonso standard v3: illustrative batch trace Stages over batch hours: Warm-up 10 h, Gassing 24 h with a dose every 6 h, Vent until CO2 is below 2,000 ppm, Hold 48 h, then Cool hold until the batch is closed. Pulp temperature stays in the recipe band; ethylene estimate steps to 100 ppm at each dose and returns to 0 after each completed vent. Warm-up 10 h Gassing 24 h Vent CO₂ < 2,000 Hold 48 h Cool hold until closed 10 14 18 22 26 Pulp temperature, °C pulp 20–22 °C pulp 19–21 °C air 12–13 °C no dose starts above 24 °C pulp chilling guard: cooling blocked at 10 °C 100 0 Ethylene est., ppm markers: doses, each ≥ 6 h after the previous dose start 2,000 5,000 CO₂, ppm (gassing and vent) exhaust ON at 5,000 vent complete below 2,000 after ≥ 10 min 0 12 24 36 48 60 72 84 96 Batch time, hours

Illustrative trace drawn to the recipe set points and the dosing rules. Real temperatures and CO₂ depend on the fruit, the load and the room.

Mango — Kesar standard

Version 2 · RH 85–90 % · ethylene up to 100 ppm est.

  1. 01 / Warm-up

    Warm-up

    8 h
    • Pulp 20–22 °C
  2. 02 / Gassing

    Gassing

    18 h
    • Ethylene up to 100 ppm est.
    • Pulp 20–22 °C
    • Re-dose ≥ 6 h after the previous dose start
  3. 03 / Vent

    Vent

    until CO₂ < 2,000 ppm
    • Exhaust at least 10 min
  4. 04 / Hold

    Hold

    36 h
    • Pulp 19–21 °C
  5. 05 / Cool hold

    Cool hold

    until the batch is closed
    • Set points per recipe
Pulp temperatureRecipe pulp bandEthylene est.CO₂

Scroll the chart sideways →

Mango — Kesar standard v2: illustrative batch trace Stages over batch hours: Warm-up 8 h, Gassing 18 h with a dose every 6 h, Vent until CO2 is below 2,000 ppm, Hold 36 h, then Cool hold until the batch is closed. Pulp temperature stays in the recipe band; ethylene estimate steps to 100 ppm at each dose and returns to 0 after each completed vent. Warm-up 8 h Gassing 18 h Vent CO₂ < 2,000 Hold 36 h Cool hold until closed 10 14 18 22 26 Pulp temperature, °C pulp 20–22 °C pulp 19–21 °C no dose starts above 24 °C pulp chilling guard: cooling blocked at 10 °C cool-hold set points per recipe 100 0 Ethylene est., ppm markers: doses, each ≥ 6 h after the previous dose start 2,000 5,000 CO₂, ppm (gassing and vent) exhaust ON at 5,000 vent complete below 2,000 after ≥ 10 min 0 12 24 36 48 60 72 84 96 Batch time, hours

Illustrative trace drawn to the recipe set points and the dosing rules. Real temperatures and CO₂ depend on the fruit, the load and the room.

If the power goes during a batch

Under 30 minThe batch resumes where it stopped.
30 min to 6 h, during GassingThe chamber vents, then re-doses for the remaining gassing time.
Over 6 hSafe hold: no ethylene, hold temperature, vent by CO₂. Every resume is logged.
WEB APP

Every chamber, on a phone or a desk.

One web app for desktop and phone browsers: live readings, 24 h charts, machine states, set points, schedules, manual override, batches, recipes, alarms with acknowledge, and reports. The screens below are from the demo site with simulated data.

RAC / CHAMBERS
RAC phone view: four chambers with mode, temperature, humidity, CO2 or VOC, online state and ripening stage progress.
Every chamber at a glanceMode · readings · stage · online state
RAC / BATCH
RAC phone view of a ripening batch: stage 2 of 5, Gassing, with the dosing interlock checklist and the next dose window.
Batch and dosing interlocksStage progress · seven checks · next dose window
RAC / ALERTS
RAC phone view with a Telegram alert preview: critical, gas leak detected, gas valve closed, exhaust on.
Critical alertTelegram alert preview · gas leak · valve closed
Batch view on the desktopStages · interlocks · dose log
RAC web batch page: Alphonso batch in stage 2 of 5, the seven dosing interlocks, and a dose log of two completed 5.0 L doses.
Each batch shows its stage, the seven dosing checks the controller applies, and the dose log the controller keeps.
Three rolesEnforced on the controller too
CustomerViews everything; changes ON/OFF thresholds within limits, schedules and manual override; starts a ripening batch.
InstallerAlso maps sensors to relays, direction, timing, fault and critical actions; pauses, resumes or aborts a batch.
Admin (GIZMOIOT)Also sets limits and minimum deadband, activates or deactivates, manages subscriptions.
AlertsAlarms with acknowledge in the app
Telegram Pilot
WhatsApp Planned
SMS Planned

Login with password plus a two-factor code (mandatory for GIZMOIOT admin staff). Telemetry every 30 s plus on every change.

SAFETY ARCHITECTURE

Designed to fail safely.

The app and the server only change settings within limits. The decisions that protect fruit, gas and compressors stay on the controller.

If the controller fails, the operator still runs the room.A Hand-Off-Auto switch on the power panel lets the operator run each machine by hand.

Coil-only outputs

Relays switch contactor coils and valves only, at most 2 A each through a panel MCB. They never switch the compressor directly.

Cooling does not stop over a bill

If a subscription lapses or an admin deactivates the controller, cooling keeps running in AUTO by default and the app becomes view-only.

Fail-safe gas-leak input

The gas-leak input is wired fail-safe. While it is active the ethylene valve stays closed and the exhaust is forced ON.

WORKS OFFLINE · HOSTED IN INDIA

No internet? The room keeps running.

The controller makes every control decision itself, so the internet is for visibility, not control. Your data lives on GIZMO's own server in India.

When the internet goes down

Day 0 is the moment the connection drops.

Runs without internetup to 30 days
A signed 30-day subscription lease is checked by the controller itself.
Readings and events buffered7 days, design target
Stored on the controller and backfilled when the connection returns.
  • No clock-setting screen. The controller learns time from the internet, so nobody can wind the clock back. An optional battery-backed clock chip keeps time through power cuts.

GIZMO's own server in India

Customer data is not stored on third-party clouds. Encrypted off-site backups.

Mutual-certificate TLS

Wi-Fi to the server over MQTT with TLS 1.2 and mutual certificates from GIZMOIOT's own certificate authority. Each controller can reach only its own data.

Signed commands

Every command, setting and lease is digitally signed (ECDSA P-256), carries the device ID and an expiry, and repeats are ignored.

Signed firmware updates

Over the air with A/B fallback; secure boot and flash encryption in production.

HARDWARE · REVISION A

What is in the box, and how it is wired.

Revision A is the pilot build. Specifications may change.

ProcessorDual-core 240 MHz Wi-Fi microcontroller, 8 MB flash, external Wi-Fi antenna
ConnectivityWi-Fi 2.4 GHz; RS-485 (Modbus) sensor bus
Display & keys20 × 4 character LCD, 4 buttons (Up, Down, OK, Back), buzzer, status LED
Power230 V AC, 50 Hz; industrial encapsulated 20 W power supply; worst-case draw about 5.2 W
Relay outputs7 changeover power relays with 12 V coils: 5 machine channels + ethylene valve + a hardware gas-enable relay in series
Output dutyContactor coils / solenoid valves, max 2 A per output via panel MCB
Digital inputs4 opto-isolated inputs, 12 V wetting: gas leak (fail-safe), door, overload, spare
TemperatureStainless-steel digital probes: air + up to 2 pulp probes; −10 to +60 °C; ±0.5 °C; up to 10 m cable
HumidityRS-485 Modbus probe: 0–100 % RH, ±1.8 % RH typical (lower accuracy above 90 % RH)
VOCMetal-oxide VOC sensor, shown as "VOC (EtOH-eq)", 50–5,000 ppm, trend indicator (not a lab value)
CO₂CO₂ sensor in ripening mode (used for venting)
ClockTime from the internet; optional battery-backed clock chip
EnclosureABS, IP65, about 200 × 150 × 75 mm, mounted outside the chamber
FirmwareSigned firmware updates over the air with A/B fallback; secure boot and flash encryption in production

How each machine is wired

The controller box sits outside the chamber. A power panel carries the contactors, Hand-Off-Auto switches and MCBs.

Scroll the diagram sideways →

Wiring of one machine channel Line through the panel MCB feeds the controller relay. The relay output goes to the AUTO position of the Hand-Off-Auto switch, then through the compressor overload contact 95–96 to the contactor coil and on to neutral. The HAND position takes line straight to the switch, bypassing the controller. L 230 V MCB Controller relay max 2 A HAND bypasses the controller Hand-Off-Auto AUTO OFF HAND Overload 95–96 (NC) A1 · A2 Contactor coil N
  • Each relay → Hand-Off-Auto switch (AUTO) → compressor overload contact → contactor coil. HAND bypasses the controller.
  • Sensor cables: temperature up to 10 m (shielded), humidity RS-485 5 m twisted pair, VOC 5 m shielded.
BUILT FOR

For the people who run the rooms.

Owners and operators of cold rooms and ripening chambers in India, and the installers who build them.

01 / Cold storage

Cold rooms

Air temperature, humidity and VOC held with ON/OFF thresholds and a minimum deadband per machine, and compressor protection that is never skipped.

02 / Ripening

Mango ripening chambers

Warm-up → Gassing → Vent → Hold → Cool hold from a recipe, ethylene capped at 100 ppm est., and seven checks before every dose.

03 / Sites

Pack-houses

Cold rooms and ripening chambers side by side, each with its own controller, all in one web app with alarms and reports.

04 / Trade

Traders and FPOs

A record for every ripening batch, with lot number, variety and weight, kept tamper-evident on the controller and the server.

05 / Installers

Refrigeration installers

Coil-only outputs, Hand-Off-Auto on the panel, and an installer role to map sensors to relays and set timing, fault and critical actions.

PILOT PROGRAM 2026

Bring us your cold room or ripening chamber.

Pilot program open for cold rooms and ripening chambers. Tell us what you run and where, and the GIZMO team will get back to you.

Cold storage, ripening, or both Number of chambers and their volume Approximate answers are fine
GIZMOIOT INNOVATIONS LLP SMART AUTOMATION SOLUTIONS
S.No 13/2, G No 5, Prem Kunj, Sagar Society, Bavdhan, Haveli, Pune, Maharashtra 411021
Mobile +91 78880 03666 · Landline 020 2025 6666
Web gizmoiot.com · GST 27ABAFG9551D1ZG

Pilot program 2026 · Hardware revision A · Specifications may change.

Thank you. Your pilot request is with the GIZMO team.