01
Integral secondary containment
Double-wall UL 142 construction with optional UL 2085 2-hour fire rating, so fuel is stored safely inside the building where the engine needs it.
Choose your flow class
Sized to the tank in front of you.
Select a model to see where it fits in the family. Every class shares the same filtration, controls, and enclosure — only the flow rate changes.
M500
Standard50–1000 GAL
Generator Day Tanks The M500 is a traditional day tank, which is adaptable to meet a broad range of specifications. The day tank has onboard controls, sensors, and transfer pumps to reliably refill from remote bulk storage tanks. The tanks are available as UL142 Double Wall or UL2085 Fire-Rated. Day Tank Controls interface with generator systems with High, Low, Leak Contacts or optional Modbus / BACnet connectivity. Mission Critical versions of the day tank are available with dual controls, sensors, and valves.
Approvals
UL 142 / UL 2085 Fire-Rated
Controller
C1 / C8 · UL 508A
Mounting
Generator room / vault
Best for
Larger & mission-critical engines
M5DT
Compact25–100 GAL
The compact M5DT stores engine fuel inside the building with integral secondary containment. Onboard transfer pumps, level and leak sensors, and inlet valves reliably refill it from remote bulk storage — all in the minimum footprint that fits inside a generator enclosure or room.
Approvals
UL 142 / UL 2085
Controller
C1 / C8 · UL 508A
Mounting
In generator enclosure
Best for
Single generator, tight footprint
M5GT
Sub-Base RefillTransfer unit
Sub-Base (Belly) Tank Refill The M5GT refills Generator Sub-Base (Belly) tanks from a remote fuel storage tank. The has onboard controls and transfer pumps with level sensors to mount in the generator sub-base tank. Controls interface with generator systems with High, Low, Leak Contacts or optional Modbus / BACnet connectivity. The compact assembly is degigned with minimum footprint for installtion within generator enclosures, or rooms. 5 Versions cover all Applications:
Approvals
UL 508A controls
Controller
C1 / C8 · UL 508A
Mounting
Wall / skid, tank-side
Best for
Generator sub-base (belly) tanks
M5HT
Flow-Thru · NYC10–100 GAL
Generator Header Tanks for In-Building or Rooftop Applications The M5HT is designed as a flow-thru Header Tank to provide limited quantity fuel storage for generator start and run when located in buildings or roof-tops. The system meets code requirements for NYC and other urban environments. Controls interface with generator systems with High, Low, Leak Contacts or optional Modbus / BACnet connectivity.
Approvals
UL 142 · NYC fire code
Controller
C1 / C8 · UL 508A
Mounting
In-building / rooftop
Best for
NYC flow-through fuel returns
Onboard capacity
Family span · 0–1000 GAL
0
250
500
750
1000 GAL
Shared technology
The same engineering in every tank.
02
Pre-assembled refill systems
Inlet solenoid valves, strainers, and transfer pumps arrive factory-assembled and tested to refill reliably from remote bulk storage tanks.
03
Level, leak & temperature sensing
A 4- or 5-point level sensor and leak sensor ship standard, with optional level and temperature transmitters wired to the controller.
04
C1 / C8 controls & BMS
UL 508A PLC controls with HMI. Output relays for High, Low, and Leak, plus Modbus — and optional BACnet — to building automation and generator systems.
Model comparison
The whole family, side by side.
Model
Capacity
Approvals
Controller
Mounting
Best for
M500
Standard
50–1000 GAL
UL 142 / UL 2085 Fire-Rated
C1 / C8 · UL 508A
Generator room / vault
Larger & mission-critical engines
M5DT
Compact
25–100 GAL
UL 142 / UL 2085
C1 / C8 · UL 508A
In generator enclosure
Single generator, tight footprint
M5GT
Sub-Base Refill
Transfer unit
UL 508A controls
C1 / C8 · UL 508A
Wall / skid, tank-side
Generator sub-base (belly) tanks
M5HT
Flow-Thru · NYC
10–100 GAL
UL 142 · NYC fire code
C1 / C8 · UL 508A
In-building / rooftop
NYC flow-through fuel returns
All models filter water + particulate to 1 micron · ISO 18/16/13 · NEMA 4 (IP65) · C81 controller, BACnet / Modbus
Built for in-building fuel
Safe storage and reliable refill, right at the engine.
Safe fuel storage inside buildings
Integral secondary containment stores engine fuel safely within the building, where the generator can reach it instantly.
Reliable refill systems
Pre-assembled, tested inlet valves, transfer pumps, and sensors are monitored and controlled by the C1 or C8 panel.
Integrated with building systems
Advanced controllers relay tank status to BAS, generator controls, switchgear, security, and fire-alarm systems.
Readily adapted for special operation
Dual inlet valves, monitored positions, overflow pumping, emergency evacuation, auto-commissioning, and fluid metering.
Equipment & options
Configured for your install.
Every M5 Series tank ships with a complete valve, gauge, and sensor package, and adapts to the code, capacity, and control requirements of the site.
Standard equipment
Inlet solenoid valve, strainer & ball valve
Transfer pump(s) with overfill-return pump
4- or 5-point level sensor + leak sensor
Standard & emergency vents
Direct-read level gauge
Inspection port, fill cap, supply & return connections
Options
UL 2085 2-hour fire rating
Level & temperature transmitters
Modbus / BACnet connectivity
Dual inlet valves, monitored position
High-level / overflow pumping
Auto-commissioning & fluid metering