Safety and Protection Solutions

Product

Product

Safety and Protection Solutions

Panel-mounted voltage presence indicator with integrated test points for live panel verification.

A certified safety device that positively verifies the absence of voltage before panel access.

Continuously monitors the integrity of the NER that connects the neutral point of a transformer to earth.

Customisable DC contactors and disconnectors engineered for rail, energy, automation, and motor control applications.

Surge protection device for motors, transformers, and generators vulnerable to circuit switching and transient voltages.

Type

Voltage Test Indicator (VTi)
Absence of Voltage Tester (i-AVT)
I-Gard Sigma 3 NER Monitoring Relay
Telarc Contactors
ZORC High-Frequency Surge Suppressor

Safety and Protection Solutions

Panel-mounted voltage presence indicator with integrated test points for live panel verification.

A certified safety device that positively verifies the absence of voltage before panel access.

Continuously monitors the integrity of the NER that connects the neutral point of a transformer to earth.

Customisable DC contactors and disconnectors engineered for rail, energy, automation, and motor control applications.

Surge protection device for motors, transformers, and generators vulnerable to circuit switching and transient voltages.

Type

Voltage Test Indicator (VTi)
Absence of Voltage Tester (i-AVT)
I-Gard Sigma 3 NER Monitoring Relay
Telarc Contactors
ZORC High-Frequency Surge Suppressor

Model: Voltage Test Indicator (VTi)

Type: Voltage Tester Indicator

Brand: I-Gard (Canada)

Model: VTi

Voltage Range: Up to 1,000VAC/VDC

Function: Confirms presence of voltage

LED Indicators: Red (Voltage present)

Mounting: Panel or enclosure door

Model: Absence of Voltage Tester (i-AVT)

Type: Absence of Voltage Tester

Brand: I-Gard (Canada)

Models: i-AVT-N / i-AVT-N Plus

Voltage Range: Up to 690VAC

Function: Confirms absence of voltage

LED Indicators: Green (Safe), Yellow (Caution), Red (Voltage present)

Operation: Capacitor powered – continues after disconnection

Mounting: Panel or enclosure door

Model: I-Gard Sigma 3 NER Monitoring Relay

Type: Neutral Earth Monitoring

Brand: I-Gard (Canada)

Model: SIGMA 3

System Voltage Range: 3.3kV to 66kV

Control Power: 110–240VAC/VDC

Maximum Time Delay: 9.3 seconds

Operating Temperature: -40˚C to +60˚C

Model: Telarc Contactors

Type: Contactors and Disconnectors

Brand: Telarc (Italy)

Models: S Series, T Series, R Series, HB Series

Voltage Rating: Up to 4,000VDC / 4,000VAC (model dependent)

Current Rating: 60A – 5,000A (model dependent)

Ingress Protection: As required (standard enclosures or IP-rated available)

Mounting: Panel or machine mounting options available

Materials: Industrial-grade housings with stainless options available

Standards: IEC 60077 (rail), IEC 60947 (low-voltage switchgear)

Model: ZORC High-Frequency Surge Suppressor

Type: Surge Suppressor

Brand: Strike (South Africa)

Models: ZORC-1Ph / ZORC-3Ph / ZORC-Compact

Voltage Range: 400V – 40kV

Mounting: Machine or panel mount

Features: Zinc oxide resistor + internal capacitor (ZORC = ZnO Resistor Capacitor)

Maintenance: Minimal, no moving parts

Application: Motors, transformers, generators

Specification

Voltage Test Indicator (VTi)

Absence of Voltage Tester (i-AVT)

I-Gard Sigma 3 NER Monitoring Relay

Telarc Contactors

ZORC High-Frequency Surge Suppressor

Model: Voltage Test Indicator (VTi)

Type: Voltage Tester Indicator

Brand: I-Gard (Canada)

Model: VTi

Voltage Range: Up to 1,000VAC/VDC

Function: Confirms presence of voltage

LED Indicators: Red (Voltage present)

Mounting: Panel or enclosure door

Model: Absence of Voltage Tester (i-AVT)

Type: Absence of Voltage Tester

Brand: I-Gard (Canada)

Models: i-AVT-N / i-AVT-N Plus

Voltage Range: Up to 690VAC

Function: Confirms absence of voltage

LED Indicators: Green (Safe), Yellow (Caution), Red (Voltage present)

Operation: Capacitor powered – continues after disconnection

Mounting: Panel or enclosure door

Model: I-Gard Sigma 3 NER Monitoring Relay

Type: Neutral Earth Monitoring

Brand: I-Gard (Canada)

Model: SIGMA 3

System Voltage Range: 3.3kV to 66kV

Control Power: 110–240VAC/VDC

Maximum Time Delay: 9.3 seconds

Operating Temperature: -40˚C to +60˚C

Model: Telarc Contactors

Type: Contactors and Disconnectors

Brand: Telarc (Italy)

Models: S Series, T Series, R Series, HB Series

Voltage Rating: Up to 4,000VDC / 4,000VAC (model dependent)

Current Rating: 60A – 5,000A (model dependent)

Ingress Protection: As required (standard enclosures or IP-rated available)

Mounting: Panel or machine mounting options available

Materials: Industrial-grade housings with stainless options available

Standards: IEC 60077 (rail), IEC 60947 (low-voltage switchgear)

Model: ZORC High-Frequency Surge Suppressor

Type: Surge Suppressor

Brand: Strike (South Africa)

Models: ZORC-1Ph / ZORC-3Ph / ZORC-Compact

Voltage Range: 400V – 40kV

Mounting: Machine or panel mount

Features: Zinc oxide resistor + internal capacitor (ZORC = ZnO Resistor Capacitor)

Maintenance: Minimal, no moving parts

Application: Motors, transformers, generators

Details

Use Case: Panel Safety Verification

The VTi is used by technicians to confirm the presence of live voltage before panel access. Installed on electrical enclosure doors, it offers a reliable, always-on visual cue for live conditions on each phase and ground.

Built-In Test Points for Fault Finding

Unlike simple voltage indicators, the VTi includes door-mounted high-impedance test points. These allow safe troubleshooting using a standard voltmeter while the panel remains closed — reducing risk during fault isolation.

Upgrade Path: i-AVT-N Plus

For enhanced verification, the VTi can be combined with the I-Gard i-AVT-N absence of voltage tester into a single integrated unit. The i-AVT-N Plus confirms both the presence and verified absence of voltage for safe work practices.

Use Case: Safety Before Panel Access

The i-AVT-N is used during lock-out/tag-out (LOTO) procedures or electrical maintenance to confirm a de-energised state before switchboard access. It adds a critical safety layer beyond traditional LED indicators.

Standard i-AVT-N Unit

Unlike indicators that show voltage presence, the i-AVT-N confirms total absence of voltage – offering a certified and auditable verification step for maintenance teams. It operates even after disconnection, powered by an internal capacitor for post-shutdown testing.

Upgrade to i-AVT-N Plus

For added functionality, Fortress also offers the i-AVT-N Plus – a combined solution that includes both a presence indicator (VTi) and absence verification (i-AVT-N) in one enclosure, giving full visual and test capability from a single access point.

Use Case: Real-Time NER Integrity Verification

The SIGMA 3 is designed to confirm continuity through the Neutral Earthing Resistor (NER), providing assurance that ground fault limitation systems are operating correctly.

The New SIGMA 3 Flagship

The key advancement in SIGMA 3 is its use of high-frequency AC injection instead of DC injection. Traditional DC-based systems risk inaccurate readings due to VT shorting paths. By contrast, SIGMA 3 ensures continuity checks are precise and bypass-safe, preserving system integrity during normal operation.

Easy to Use TDM

Each SIGMA 3 comes with a panel-mounted Touchscreen Display Module (TDM) for local monitoring and simple parameter configuration, streamlining operations and diagnostics.

Use Case: High-Reliability DC Switching

Telarc contactors and disconnectors are designed for demanding switching applications across industries including rail, energy, automation, and motor control.

Standard Telarc Products

The R Series serves as a drop-in replacement for legacy ABB R-Type bar contactors, and the HB Series supports high-speed DC protection in battery and traction systems. Fortress also offers the full S and T Series for DC contact and disconnection, all compliant with IEC 60077 standards.

Telarc Options

Fortress can supply custom Telarc units tailored to mounting constraints, current and voltage levels, or sensing needs. Available options include auxiliary contact layouts, integrated voltage or current sensors, and mechanical adaptations for space-constrained installations.

Use Case: Motor and Transformer Protection

Prevent internal winding damage, reduce insulation stress, and extend the lifespan of generators, motors, and VFD-equipped equipment.

Standard ZORC Units

The ZORC is a high-frequency surge suppressor designed to protect motors and other inductive loads from steep-fronted transients caused by switching. Fortress offers the compact ZORC in single-phase and three-phase models.

Bespoke ZORC Options

Clients can select from ZORC-1Ph (single phase), ZORC-3Ph (three phase), and ZORC-Compact for tight installs. Mounting can be machine-side or panel-side. Voltage ranges span from 400V up to 40kV.

We’re here to answer all your questions

Got questions? We’ve got answers! Below are some of the most common inquiries about our products and services. If you don’t find what you’re looking for, feel free to reach out to our team—we’re happy to help!

What extra functionality does the VTi offer over a simple indicator?

It provides door-mounted test points for safe voltage measurement alongside LED indicators for live status.

Is the VTi touch safe?

Yes – its high-impedance design limits current to 1.8mA, well below electrical shock thresholds.

Can it be used with an absence of voltage tester?

Yes – the VTi integrates with I-Gard’s i-AVT-N, or can be supplied as part of the i-AVT-N Plus combined system.

What are the relevant standards?

The VTi is designed to meet IEC 61010-1 and IEC 61010-2-30.

How is this different from a voltage indicator?

Voltage indicators confirm the presence of voltage. The i-AVT-N goes further by verifying true absence – essential when no LED alone can be trusted.

Does it work when the system is powered down?

Yes – it retains charge for up to 15 hours after power loss and recharges in 20 minutes via onboard USB-C.

How does it ensure results are reliable?

The i-AVT-N is SIL3 compliant and uses dual sensor leads for each phase, neutral, and ground to eliminate false positives.

Can I use this with a voltage indicator?

Yes – it pairs with I-Gard’s VTi and is fully integrated in the i-AVT-N Plus.

What are the relevant standards?

The i-AVT-N meets UL1436 and is compliant with IEC 61508, IEC 61000-4-5, IEC 61326 and IEC 61010-2-30.

How does the SIGMA 3 Relay function?

It measures NER current, neutral-to-ground voltage, and resistance. It compares those against set thresholds and triggers outputs or LED alerts when anomalies are found.

What other items are required for a complete SIGMA 3 NER Monitoring System?

You’ll also need the matching I-Gard Sensing Resistor and Current Sensor – both available from Fortress.

Can I still purchase the original SIGMA Relay?

Yes – legacy SIGMA relays are available as replacement units.

What is the minimum resistance that can be monitored?

SIGMA 3 can monitor NER resistance as low as 6 Ohms effectively.

Can this be used in mining environments?

Yes – it meets the requirements of AS/NZS 2081:2018.

What information do I need to get a quote?

To provide a quote, we’ll need:

System voltage

Current or resistance requirement

Which Telarc products can Fortress supply?

Fortress supplies the full Telarc range throughout Australia and New Zealand, including all S, T, R, and HB Series contactors, disconnectors, and breakers.

Is there a direct replacement for ABB R-Type contactors?

Yes. Telarc’s R Series is fully compatible with ABB bar contactors. Matching FPL codes ensure seamless retrofit of IOR, NOR, JOR, FOR, and LOR types.

Can Telarc contactors be customised?

Yes. Options include auxiliary contact customisation, integrated voltage/current sensors, and tailored mechanical mounting designs.

What information do I need to get a quote?

You’ll need to provide your required current and voltage ratings, plus any space or cabling limitations. This ensures we deliver an optimised, fit-for-purpose solution.

Is the ZORC a lightning arrester?

No – it is for high-frequency transient voltages, not direct lightning strikes.

Why is capacitance important?

The ZORC’s internal capacitor filters fast transients that other devices might miss.

Can it be installed close to the motor?

Yes. It can be installed directly at the load or in the nearest panel

What are the maintenance requirements for ZORC units?

The ZORC is maintenance-free, requiring only periodic visual inspection and cleaning of bushings in contaminated areas

What information do I need to get a quote?

By providing the information listed below a complete quote can be supplied:

System Voltage
Number of Phases
Intended mounting location

Safety and Protection Solutions

Type

Safety and Protection Solutions

Type

Model: Voltage Test Indicator (VTi)

Model: Absence of Voltage Tester (i-AVT)

Model: I-Gard Sigma 3 NER Monitoring Relay

Model: Telarc Contactors

Model: ZORC High-Frequency Surge Suppressor

Specification

Model: Voltage Test Indicator (VTi)

Model: Absence of Voltage Tester (i-AVT)

Model: I-Gard Sigma 3 NER Monitoring Relay

Model: Telarc Contactors

Model: ZORC High-Frequency Surge Suppressor

Details

We’re here to answer all your questions

Contact Our Technical Team

Get in Touch with Us