Here are a few commonly asked questions:

Your controller must be version 3.06 or higher. Network printing also requires a registration code which can be obtained from TotalTemp Technologies or Tidal Engineering for a nominal fee. Free firmware updates available, easily installed from the front panel USB port.

The circuit breaker switch at the rear of the controller must be on in order to control temperature. It is good practice to always leave this circuit breaker ON. You can turn it off for purposes such as testing communication functionality.

Earlier platforms do not have the indication of the state of the thermal safety switch in the platform. If there is no indicator or the red LED is on, turn the power off, allow the platform to cool slightly then turn back on.

Verify that the smaller 'sensor' connector is properly connected to the platform. Clear prior alarm conditions on Synergy from the Maintenance -> Alarms menu on the front panel.

Press the 'RESET' button on the Watlow controller to clear the 'err' message. If the temperature is indeed out of range, the temperature must be back in range before proceeding.

TotalTemp makes a customized version of our controllers to be compatible with Sigma Systems thermal platforms. Consult factory regarding compatibility details.

Expendable cryo coolants (L-CO2 or L-N2) are generally faster. High-pressure L-CO2 is a good option for intermittent use because it stores indefinitely in the tank at room temperature. Cryogenically cooled platforms are cheaper to buy than systems with refrigeration. They can also save money in making test times shorter with faster cycling. According to our math and years of experience, we see Cryo systems as generally cheaper in the long run. Change here -> First, they are much more inexpensive to buy and maintain, but, they do not require the ongoing expense of expendable coolant. Mechanical refrigeration systems make motor noise and can expel significant heat into the room unless a water-cooled option is used. All other things being neutral, TotalTemp generally recommends High-Pressure L-N2 for overall ease of use, reliability, efficiency, and speed. Single-stage refrigeration systems typically have a lower temperature limit of -40°C. More expensive two-stage cascade systems typically have a lower temperature range of -65-80°C. L-CO2 systems typically go as cold as -65°C. L-N2 systems go as cold as -100°C. Low-pressure L-CO2 and L-N2 are generally recommended only if you already have that kind of coolant in use or have a distribution system in place.

General safety precautions should be followed when servicing compressed gas connections. There are several things to note with cryogenic exhaust gases. First, the amount of exhaust our platforms expel is minimal. As compared to a chamber they are much smaller and more efficient with the use of the cryogenic liquid coolant. Also, the platforms are expelling exhaust only during the cooling cycle, or periodically during cold soaks to maintain temperature. So, generally speaking, the amount of exhaust expelled from one platform is not enough to cause any issues with the safety of the breathable air. Even several platforms in a normal size room with the usual typical venting found in most buildings would unlikely ever cause a problem. You would have to have many platforms in a small unvented room to ever cause concern. With L-N2, the exhaust is nitrogen gas which is 80% of the normal air we breathe every day. The only concern with that exhaust is oxygen displacement, where so much nitrogen gas might be expelled that the oxygen levels reach unsafe low limits. This can easily be monitored with an O2 detector which doesn’t cost that much if there is a concern. With L-CO2, the exhaust is carbon dioxide which of course is not something you want to breathe in high concentrations. As stated above, it would take many platforms before that becomes an issue.

Temperature chambers are widely used to simulate the thermal environmental conditions an item will be exposed to and expected to continue operating properly. Resistance heaters in the airflow are used to heat and cooling is performed by a few different methods, direct injection of coolant such as Liquid Nitrogen / liquid CO2 or a refrigeration system, in some cases simple air cooling. A programmable temperature controller is used to monitor temperature, control heating / cooling to maintain temperature and safety.

A good programmable temperature controller can be easily set to determined high and low ranges including safety limits for the thermal test. Temperatures can be set manually, through a stored temperature profile or as instructed via computer interface.

Temperature cycling refers to repeatedly transitioning between two or more temperatures, generally in an effort to simulate or slightly exceed conditions expected in the use of the item. Thermal shock usually refers to transitioning temperature as quickly as possible or at a very fast controlled rate. Thermal shock can also refer to applying hot temperatures and cold temperatures simultaneously to the same device such as is possible with the Hybrid Benchtop Chamber or dual zone thermal platform.

TotalTemp offers accessible phone support and service parts everyday. Thermal platforms and controllers can be sent to the factory if service is required. Larger units must be serviced on site at the discretion of TotalTemp Technologies.

Maintenance is not normally included with the purchase of the products. Two year warranty coverage of failures that are due to workmanship or component failures which are not a result of misuse is included.

The only maintenance item of a thermal platform is the solenoid valve(s). Typically they are good for 10 million cycles so they are expected to last several years at which point they can be rebuilt. The particle filter at the coolant inlet of expendable coolant systems should be checked if particle contamination is suspected. Systems with refrigeration systems must always be checked to make sure lint contamination is not blocking the air heat exchangers. Inspection frequency depends on the level of contamination of the local air source.

Yes, that is what they are designed to do, to allow more capacity in less space. When used with a dual zone controller, they remain independent in their operation. They are often configured to allow a safety related event to shut down both chambers.

We recommend that products built to be operated in high altitude or space should be tested in the environment that they are intended to operate in. TotalTemp offers space simulation chambers capable of -75 to +175°C and 10-6 Torr vacuum.

TotalTemp is very much open to quoting on your custom thermal test equipment needs. Give us a call.

The Hybrid Benchtop chamber is designed to employ both forced air convection and conduction to force the temperature of a device to the required temperature quickly, uniformly and with intended amount of thermal stress. It can also be used for stress testing where the air temperature is set to one temperature and the platform temperature is set to another temperature.

Yes, Limit controllers are designed to shut a system off in a condition where temperature goes out of range. Usually a limit controller will have a latching function where it requires manual reset of some form to resume operation. A controller designed to control temperature is known as a PID, or Proportional Integral Derivative controller This is a simple mathematical formula that takes into account the rate of approach and how long it takes to change temperature given a specific amount of heating or cooling. Thus a PID controller can approach temperature smoothly and hold more accurately.

Thermal platforms often are sold with a built in limit controller for safety. The temperature controller itself has safety limits built in and a limit controller can be used to provide an additional level of safety. For example if you remove power from a heater, it will always stop heating. If you remove power from a stuck-open coolant valve, the coolant flow is likely to continue to flow if power is removed from the valve. A popular option for unattended testing is to have a limit controller, controlling a secondary, series solenoid valve in the coolant circuit to prevent run away cooling and potentially protect personnel / expensive equipment under test.

As a rule of thumb thermal test designers will place the sensor as near as possible to sources of heat or cooling source. Likewise, in a temperature chamber, locate a sensor at a blower outlet or location where airflow is the greatest. Low mass temperature sensors should also be used to reduce lag between heating and heat detection. Likewise, especially with temperature chambers lower mass heaters directly in the airflow respond with less lag.

We can install new controllers, particularly the Synergy Nano into existing chambers however we often aren't able to reasonably travel to other locations. We have a network of engineering companies that might be able to help you get an older chamber going with a new controller. Call us.

Generally PID parameters are set at the factory to be optimized for the system it was shipped with. Normally no further adjustment is required if the controller is kept with the rest of the system, however things like different coolant pressure or application of a massive load might be optimized with the parameters adjusted a little.

We don't really specify a calibration interval for our equipment. The controllers typically hold calibration very well. Once every one or two years is a good recommendation to make sure things are performing as expected.

Warranty Policy is on the website, The warranty is for two years, valves are a wear item, thus excluded from warranty as are items that were abused. TotalTemp makes a good faith effort to fairly cover warranty items in a timely manner.

Vacuum jacketed LN2 delivery hose is always recommended for delivery of liquid Nitrogen to avoid losses because it is so extremely cold, to reduce lag time for liquid coolant to reach the device, and also to reduce any possible hazard due to condensation that might produce puddles on the floor. Regular, foam insulated hoses can be used. In any event, a hose with a pressure relief valve is recommended. High quality Silicone “Heater hose” can be used as an exhaust but never flex an exhaust hose when it is cold.

People often specify an adapter plate on top of their platform to allow easy fixturing of devices to the platform and reduce the risks involved with drilling directly into the platform surface. Good clamping force allows good heat transfer. There are many areas of the platform surface where damage could occur by drilling as little as ⅛ deep. Be aware that the mass of a ¼ adapter plate can easily slow down the heating and cooling rates by 20%.