Heat Mat Box

Model: HMB

Heat Mat Box

Model: HMB
Automatic control with a six-step growth curve

The Heat Mat Box is an automatic temperature-based control with one 20 amp variable stage designed to control heat mats.

Powerful, yet easy to use

The Heat Mat Box is loaded with powerful features, including a six-step growth curve. All control functions are never more than a few button presses away, making the Heat Mat Box one of the easiest controls to program.

Peace of mind

The Heat Mat Box displays temperature, mode, alarm, and status information. Monitoring the control regularly gives you a better idea of what is going on with your equipment and in your facility.


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SKU: HMB Category:
  • Automatic temperature-based control, programmable
    range: 70 to 125°F (21 to 51°C)
  • Six-step growth curve, up to 365 days duration
  • Manual override mode
  • Variable heating stage for controlling heat mats
  • Alarm relay for triggering external alarm system or siren
  • Temperature sensor input
  • Minimum and maximum temperature logging
  • Large 20-character, 4-line LCD display
  • Alarm message display
  • Power-failure settings protection
  • NEMA 4X enclosure (Corrosion-resistant, water-resistant,
    and fire-retardant)
  • CSA approval
  • Limited warranty
  • Incoming power
    120/230 VAC, 50/60 Hz
  • Control fuse
    250 V, 1 A fast-acting glass
  • Variable stage
    20 A at 120/230 VAC, general-purpose (resistive)
    2300 W at 120 VAC; 4600 W at 230 VAC
  • Alarm relay
    0.4 A at 125 VAC, 2.0 A at 30 VDC, resistive load
    0.2 A at 125 VAC, 1.0 A at 30 VDC, inductive load

Variable Load Expansion Box

Variable Load Expansion Boxes increase the load capacity of the control's variable stage. Installation is simple and there is no additional configuration required; all Expansion Boxes follow the settings of the master control.

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Heat Mat Box settings saver

The HMB Saver is an innovative and easy-to-use product that allows you to store all your Heat Mat Box configuration and settings. You can restore them at any time, or use the HMB Saver to set up new controls in seconds.

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Heat Mat Box Firmware updater

The HMB Updater lets you upgrade your Heat Mat Box's firmware with new features as they become available. The HMB Updater takes only seconds to use and can upgrade all the Heat Mat Boxes at your site.

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Bottom Board Kit for HMB | HMC

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Display Kit | HMB

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Ten pack of 1 A fuses

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How big is the control?

The enclosure is 9 x 7 x 3.75 inches (23 x 18 x 9.5 cm). The heatsink adds an additional 1.25 inches (3.5 cm) to the width.

Does it have a manual override?

Yes. There is a software manual override that can be accessed through the control’s menu. For more information see Using manual override mode in the user manual.

How many expansion boxes can you connect to a single HMB?

You can connect up to three expansion boxes to each HMB.

Does the HMB need to be connected to the same phase of power as the heat mat in a 3-phase system?

Yes. The HMB, heat mat, and any expansion boxes/mats all need to be connected to the same phase of power.

What mats is this compatible with?

The HMB is compatible with Hog Hearth® heat mats, as well as many other mats on the market today. It can be configured to work with mats that use 1k, 3k, or 5k sensors.


Why would I use a growth curve?

As animals grow, they require less heat from the mat. The growth curve allows you to automate this reduction in set point temperature for the mat. Think of the growth curve as a user defined schedule for reducing the set point temperature.


Why is my main control working but my Expansion Box is not?

Confirm the expansion box wiring going from the master to the expansion.

The Heat Mat Box has a connector labeled SLAVE 1 for connecting Expansion Boxes. Connect the Expansion Cable from SLAVE 1 A to SLAVE 1 B. To connect additional Expansion Boxes, connect the cable from SLAVE 1 A to SLAVE 1 B.

Why am I getting different outputs on my main box and expansion box?

Ensure that your main box, expansion box, and applicable mats are all connected to the same phase of power.

Why does my heat mat surface measure a different temperature with a temperature gun than is shown on the HMB?

Because the temperature sensor is built into the heat mat, the temperature it measures may be different than the actual mat surface temperature. Use the Sensor Correction setting to adjust the HMB reading to match the temperature gun reading. The default setting adjusts the reading to work with Hog Hearth® heat mats. For more information see Setting the sensor correction value in the user manual.