Question 1

What is the GTM series and why is it considered a breakthrough technology?

Accepted Answer

The GIGAVAC GTM series is the new-generation hermetic DC contactor family Sensata Technologies launched at The Battery Show North America in 2023. Its key innovation is GTMS (Glass-to-Metal Sealing) — an industry-first sealing technology applied to a contactor. GTMS brings Sensata's 50+ years of aerospace, military and industrial sealing expertise into contactor design. The architecture combines the best of traditional ceramic and epoxy-to-metal sealing — outperforming earlier sealing approaches on breaking performance, thermal withstand and overall ruggedness. The series targets energy storage systems (ESS), high-power DC fast-charging stations, heavy-duty EVs and V2G applications.

Question 2

What is GTMS (Glass-to-Metal Sealing) and how does it differ from ceramic sealing?

Accepted Answer

GTMS stands for "Glass-to-Metal Sealing." It is the technique Sensata has used for 50+ years in aerospace, military and industrial applications to form an electrically highly insulating hermetic seal. Compared to traditional contactor sealing technologies:

• Ceramic sealing (e.g. EPIC®): High dielectric strength, compact and light — but complex and costly to manufacture.
• Epoxy-to-metal sealing: More economical, but not as durable as ceramic at high temperature and high voltage.
• GTMS (Glass-to-Metal): In Sensata's own words, "combines the best of traditional ceramic and epoxy-to-metal sealing." Delivers high dielectric strength, high-temperature and mechanical-stress withstand and aerospace-grade reliability.

The series is the result of porting Sensata's 50-year aerospace GTMS heritage into contactor design.

Question 3

Which models are in the GTM series?

Accepted Answer

The GTM series currently includes two models:

• GTM400 — 400 A continuous, 1500 Vdc
• GTM500 — 500 A continuous, 1500 Vdc

Both models are fully bidirectional and share the same GTMS sealing technology. Sensata's stated vision is to extend the GTM family into lower-power applications such as AGVs, material-handling equipment and 2-3 wheeler EVs — so the GTM series will continue to grow.

Coil voltage options: 12 Vdc and 24 Vdc. Coil termination is offered as flying leads in 10 in (≈254 mm), 22 in (≈559 mm) and 46 in (≈1168 mm). Auxiliary contact options: None / SPST-NO / SPST-NC / SPDT.

Question 4

What is fully bidirectional switching and why does it matter?

Accepted Answer

Fully bidirectional switching means the contactor breaks current with equal performance and reliability in both directions. Most DC contactors are optimised for one current direction; arc suppression can be insufficient under reverse current. The GTM series' fully bidirectional design is critical for:

• V2G (Vehicle-to-Grid) systems — the main contactor that lets an EV battery feed power back to the grid
• Hybrid ESS — the same contactor is used in both charge and discharge modes
• Bidirectional DC-DC converter applications
• Solar + battery hybrids — charge during the day, discharge at night

V2G — the backbone of modern grid-interactive energy infrastructure — is simply not possible without fully bidirectional contactors like the GTM.

Question 5

Where is the GTM series used?

Accepted Answer

The GTM series is designed for high-power DC switching and circuit protection applications:

• Energy Storage Systems (ESS) — utility-scale and commercial connect/isolate
• High-power DC fast-charging stations (350 kW+ and megawatt charging)
• Heavy-duty EVs — trucks, buses, off-highway
• V2G (Vehicle-to-Grid) systems — vehicle ↔ grid power flow
• Solar inverters and combiner boxes — utility-scale PV
• Battery packs — high-voltage BMS connect control
• HVDC industrial drive systems
• DC arc-fault interrupter systems — protection applications

Sensata's roadmap includes new variants for AGVs, material handling and lighter EVs.

Question 6

Why does the GTM series not require PWM electronics? How does the dual-coil design work?

Accepted Answer

One of the GTM series' key innovations is a low-power hold mechanism that does not need PWM electronics. How it works:

1. Pick-up: Both coils energise together to close the contactor with full force.
2. ~75 ms later: One coil is electronically dropped from the coil driver.
3. Hold: The remaining coil keeps the contactor closed at low power — within full spec.

The payoff is that the issues created by traditional PWM drivers disappear: no EMI emissions, no cross-talk on the control supply, clean and quiet coil drive. For continuously energised applications like ESS this delivers both energy savings and EMC compliance benefits.

Question 7

What is a mechanically linked auxiliary contact?

Accepted Answer

The GTM auxiliary contact is mechanically linked to the main contacts. That means the real position of the main contact (open/closed) is physically confirmed by the auxiliary — not by an electrical proxy.

This matters most in safety-critical applications:
• Closed-position confirmation of the main contact
• Reliable feedback in E-stop circuits
• Main-contact state to BMS and protection relays
• Functional safety applications (SIL / PLd-level systems)

Aux contact ratings: 2 A 24 Vdc resistive, 100,000 cycles, minimum 10 mA / 5 V. The SPDT (both NO and NC) option offers maximum flexibility.

Question 8

What certifications does the GTM series carry?

Accepted Answer

The GTM series targets the following certifications and standards:

• UL and CE approval — industrial and commercial acceptance (Sensata XML lists this as "UL and CE planned"; current certificate status should be confirmed with Sensata tech support)
• Exceeds IP67-69 specifications — suitable for outdoor environments
• Hermetic seal — no risk of arc ignition in outdoor air

The GTMS sealing technology underlying the GTM series comes from Sensata's 50+ years of certified aerospace and military expertise. For specific project certification requirements, a Sensata tech-support review is recommended.

Question 9

How is the GTM series used in energy storage systems (ESS)?

Accepted Answer

The GTM series is purpose-built for modern energy storage systems. Typical ESS roles:

• Main battery connect/isolate contactor — controls the ESS battery's connection to the inverter
• String isolation — one contactor per string in paralleled ESS strings
• Charge/discharge transition contactor — its bidirectional design handles both legs with a single model
• Faulty module isolation — removes a failed battery module from the system

GTM's 1500 Vdc rating fits the standard voltage level of modern utility-scale ESS. The PWM-free low-power hold reduces annual energy consumption for continuously energised ESS connect contactors and does not generate EMI.

Question 10

What role does the GTM series play in high-power DC fast-charging stations?

Accepted Answer

High-power DC fast-charging stations (350 kW and above, megawatt charging) are an ideal application space for the GTM series. Typical uses:

• Charge cable output contactor — main break between the cable and the vehicle battery pack
• DC bus isolation — separating DC bus segments inside the station
• E-stop circuits
• Faulty charge termination — fast-break fault scenarios

The 1500 Vdc rating is compatible with modern megawatt charging (MCS), which requires 1500 Vdc / 3000 A infrastructure. GTM's fully bidirectional design provides a single-model solution for V2G-capable stations.

Question 11

When should I choose the GTM series over other GIGAVAC families?

Accepted Answer

The choice depends on the technology requirement and the cost/performance balance:

• GTM series — Where new-generation GTMS sealing is wanted, V2G / bidirectional is critical, and the use case is ESS, high-power DC fast charging or heavy-duty EVs with the highest reliability bar.
• HX series — 1500 Vdc utility-scale solar and EV bus/truck, EPIC® patented ceramic sealing, best-in-class voltage + current performance.
• GX series — 800 Vdc EV main power contactor, 26 model variants, the general-purpose flagship.
• GV series — Economical high performance, many variants, broad 100-1000 V range.

The GTM series is positioned as the standard new-generation choice for post-2023 V2G-capable ESS, megawatt-charging and heavy-duty EV projects.

Question 12

What is the maximum operating temperature of a GTM contactor?

Accepted Answer

The GTM series operates from -40 °C to +85 °C under standard conditions. Sensata datasheets state operation up to 125 °C in special applications — provided terminal temperature stays below 150 °C and subject to Sensata tech-support review. High-temperature withstand is a strength inherited from GTMS' aerospace heritage. It is especially valuable inside ESS modules, in heavy-duty vehicle motor compartments and in high-ambient industrial applications.

Question 13

What is the launch date and roadmap of the GTM series?

Accepted Answer

Launch timeline:

• September 2023: Sensata Technologies officially launched GTM400 and GTM500 at The Battery Show North America (Novi, MI).
• 2024-2025: The series went into ESS, DC fast-charging and heavy-duty vehicle projects.

Sensata's stated roadmap (Justin Colson, VP Clean Energy Solutions): extend the GTM family into lower-power applications — new variants for AGVs, material handling, 2-3 wheeler EVs and other EV use cases. The GTM is positioned as a rapidly growing, expanding new-generation contactor family.

Question 14

How is the GTM series sourced in Türkiye, and what is its pricing?

Accepted Answer

Because the GTM is a new family, lead times vary by project; standard variants are available from Sensata global stock. As GIGAVAC's authorised distributor in Türkiye, IMB Electric handles stock checks, pricing and technical support. The GTM series sits in the premium tier given its new-generation technology positioning — but on a lifecycle-cost basis for ESS and fast-charging projects, the reliability advantage of GTMS makes it a competitive choice. Special pricing and application engineering are available for project-based high-volume orders.

About the GTM Series series

01What is the GTM series and why is it considered a breakthrough technology?

02What is GTMS (Glass-to-Metal Sealing) and how does it differ from ceramic sealing?

03Which models are in the GTM series?

04What is fully bidirectional switching and why does it matter?

05Where is the GTM series used?

06Why does the GTM series not require PWM electronics? How does the dual-coil design work?

07What is a mechanically linked auxiliary contact?

08What certifications does the GTM series carry?

09How is the GTM series used in energy storage systems (ESS)?

10What role does the GTM series play in high-power DC fast-charging stations?

11When should I choose the GTM series over other GIGAVAC families?

12What is the maximum operating temperature of a GTM contactor?

13What is the launch date and roadmap of the GTM series?

14How is the GTM series sourced in Türkiye, and what is its pricing?