Continuous ammonia inventory monitoring — not a snapshot, a live feed
The NH3Edge edge computer connects to your existing PLCs and level instruments, runs continuous thermodynamic calculations to determine ammonia mass in each vessel, and delivers live inventory data through the IIOTK Cloud platform.
Built specifically for ammonia refrigeration — not repurposed from a generic industrial IoT platform. The calculation models, alarm logic, and compliance modules are all purpose-built for NH₃ systems and regulatory requirements.
The dashboard your team will live in
Real-time operational visibility
System Dashboard
At-a-glance KPIs: total system charge, operating pressures, vessel levels, alarm status, and compliance indicators. The operational overview you've never had before.
Interactive P&ID Flow Diagram
Live flow diagram showing actual operating values at each instrument point. See exactly where your ammonia is at this moment — which vessels are heavy, which are light.
Historical Trends
Trend any process variable over time. Understand how your inventory shifts between seasons, under different production loads, and when condensers cycle. Data retention configurable.
Active Alarm Monitoring
Configurable alarm limits for inventory threshold proximity, pressure exceedances, and instrument health. Multi-channel notification: on-screen, email, SMS with escalation chains.
Documentation that writes itself
PSM compliance requires extensive documentation. NH3Edge captures operational data and automatically generates the records your program requires.
Daily Rounds & Inspections
Guided digital walkthrough for operator inspection rounds. Field observations, equipment checks, and exception logging — all timestamped and stored.
Oil Drain Log
Automated oil drain event tracking with quantity, vessel, and technician documentation. Maintains the ongoing oil drain records required by IIAR Bulletin 110.
Ammonia Charge Ledger
Complete inventory event tracking: additions, removals, purger events. The running charge account that documents your regulatory threshold position over time.
Auto Purger Activity
Automatic logging of purger cycles with ammonia quantity, timestamp, and cumulative totals. Required documentation made automatic.
PRV Management
PRV register with all sizing calculations, test dates, set pressures, and next inspection scheduling. Currently showing 15 items needing attention across tracked facilities.
Safety Testing Schedule
Track all required safety system tests — low-level shutoffs, high-pressure cutouts, emergency stops — with scheduling, completion recording, and overdue alerts.
Personnel Management
Maintain the authorized personnel list, training records, and qualification documentation required by PSM Element 5 (Training) and Element 6 (Contractors).
How NH3Edge calculates ammonia mass
Level measurement → Liquid volume
Level instruments (guided wave radar, magnetostrictive, or differential pressure) measure liquid level in each vessel. NH3Edge converts level percentage to liquid volume using stored vessel geometry (diameter, length, head type).
Pressure measurement → Operating temperature
Pressure transducers measure operating pressure in each vessel. NH3Edge looks up the saturation temperature corresponding to that pressure using built-in ammonia thermodynamic property tables (ASHRAE/NIST data).
Temperature → Liquid density
At the saturation temperature, NH3Edge retrieves the saturated liquid density of ammonia from the thermodynamic property tables. This density accounts for the actual operating condition, not standard conditions.
Volume × Density → Mass
NH3Edge multiplies the calculated liquid volume by the liquid density to determine the mass of ammonia in each vessel. Vapor mass is calculated separately using vapor density at operating conditions and vapor volume.
Sum across all vessels → Total system inventory
NH3Edge sums the ammonia mass across all monitored vessels (plus piping estimates from flow model) to determine total system inventory. This value is displayed live, trended, and compared against the 10,000 lb threshold.
Technical Specifications
- Allen-Bradley (Ethernet/IP)
- Siemens (S7 Protocol)
- Generic Modbus TCP/RTU
- OPC-UA compatible
- Guided Wave Radar (GWR)
- Magnetostrictive
- Differential Pressure
- Pressure-based calculation
- Pressure Transducers
- RTD Temperature Sensors
- Thermocouple inputs
- 4-20mA analog inputs
- 10/100/1000 Ethernet
- Industrial hardened
- VPN-capable
- Firewall-isolated
- IP65-rated enclosure
- -20°C to +60°C operating
- DIN rail mountable
- UPS battery backup capable
- IIOTK Cloud (multi-tenant)
- Data encrypted in transit
- 99.9% uptime SLA
- Configurable data retention
Ready to see it live?
Schedule a demo and we'll walk you through the NH3Edge system using real data from a live facility (anonymized). See what your dashboard would look like.