/ RESERVE POWER · FLOODED TUBULAR STATIONARY
OPzS battery — flooded tubular cells for critical infrastructure
When a substation trips, a plant blacks out, or a grid must restart, the DC system runs on its battery — and for that duty the world’s utilities still specify flooded tubular OPzS cells. Microtex builds them in Bengaluru from 100 Ah to 3000 Ah, on the same tubular plate technology that carries our mining and traction batteries — European-class engineering without the European invoice.
Approved vendor: NPCIL · BARC · Indian oil companies — Seismically qualified (IEEE 344) — CPRI type-tested — 100–3000 Ah
What OPzS means — and why utilities still specify it
OPzS is the DIN designation for a stationary flooded cell built on tubular positive plates. The tubular plate is what earns the service life: active material is locked inside woven gauntlets around cast spines, so the cell survives decades of float duty punctuated by deep emergency discharges — the exact profile of substation, power-plant and telecom DC systems.
Flooded construction keeps the battery honest: cells you can inspect, condition you can check by direct measurement — voltage, impedance trend, specific gravity — and capacity you can prove outright with a discharge test. Where trained maintenance exists, nothing matches flooded tubular for transparent, verifiable life.
Our 2V OPzS cells are seismically qualified — Resonance Search, OBE and SSE testing per IEEE Std 344:2013 at CPRI Bengaluru, witnessed by NPCIL QA.*
FIG. 1 — 2V OPzS CELLS, 100–3000 Ah
Where our OPzS cells serve
Substations & grid
110/220 V DC banks for switchgear, protection and SCADA — the application page covers duty and sizing.
Nuclear & heavy industry
Backup duty where vendor approval is the entry ticket — Microtex is an approved vendor to NPCIL, BARC and Indian oil companies.
Power plants & industry
Emergency lighting, black-start support, DC control power — long float life with proven emergency capacity.
Solar & telecom
Deep daily cycling with maintenance staff on site — where visits are rare, see OPzV Gel instead.
Evidence, not adjectives
| Proof | Detail |
|---|---|
| Seismic qualification | Resonance Search + OBE + SSE per IEEE Std 344:2013, CPRI Bengaluru, witnessed by NPCIL QA — 2V OPzS cells in steel stand* |
| Vendor approvals | NPCIL · BARC · Indian oil companies — approved-vendor registrations held |
| Type testing | CPRI type-tested ranges; report numbers and ULRs quoted in tender documentation |
| Manufacturing | Alloys, oxide, plates, gauntlets, separators made in-house — the technology page shows how |
* TYPE TEST HELD BY MYSORE THERMO ELECTRIC PVT LTD, A MICROTEX GROUP COMPANY.
Questions tender engineers ask us
OPzS or OPzV — which should my specification call for?
Flooded OPzS where trained maintenance exists and maximum verifiable life is the goal — utilities, plants, substations. Sealed OPzV gel where the room is unmanned or visits are rare — solar, telecom, remote sites. The electrochemistry is the same tubular family; the trade is transparency versus freedom from maintenance.
What decides an OPzS battery’s real service life?
Three things the datasheet doesn’t show: charging discipline (float and equalise voltages actually held), room temperature (heat accelerates internal corrosion — every battery standard rates life at 27 °C for a reason), and watering with clean water on schedule. Bought well and treated well, flooded tubular stationary cells are the longest-lived lead-acid batteries made.
Can you meet utility and nuclear tender documentation?
Yes — that is the business we are built for: type-test reports with ULR numbers, seismic qualification records, vendor-registration credentials, installation and maintenance manuals, and factory acceptance testing with customer witness. Send the tender annexures with your enquiry.
Do you supply cells in transparent containers for inspection?
Cell containers and covers are moulded within the Microtex group, giving us control of material and clarity specifications — state your preference in the enquiry and we will confirm against the size required.
How do I size an OPzS bank for my DC system?
Send the DC system voltage window, the continuous and momentary loads, the required autonomy in hours, the room temperature, and the end-of-discharge voltage your protection scheme allows. Our engineers size to your duty and reply the same working day — use the enquiry form.
Specify a battery your successor will thank you for.
Send the duty — voltage window, loads, autonomy, room conditions — and the proposal comes back with the evidence attached.