HT-3 System Controller

HT-3 System Controller

The PULSAIR HT-3 controls up to three Horizontal Tanks, one at a time. It can be configured for remote on/off control (RC) option. PULSAIR has not made an RSC, an option that allows tank selection from a remote location. However, it is possible to build tank selection into the RSC. PULSAIR's Programmable Remote Station Controller (PRSC) could be programmed such that the operator can switch the HT-3 from one tank to another. This programming can be made without too much additional effort. Controlling three tanks with one pneumatic contrloller such as the FT-3 or HT-3 is the limit. Building a pneumatically controlled system for more than three tanks is cost prohibitive and the installation is complicated. It is more economical to use two HT-2s than a single HT-4.

For the HT-3 to be effective, the tanks must be located next to one another. This is the most important factor when recommending the unit to a customer. It is not necessary that the tanks are all the same size, although it makes the controller adjustments easier. For instance, the Dwell may need to be adjusted when switching from a large to a small tank.

Furthermore, because the injection time and system performance is affected by the distance between the injection valves and the controller, it is important that all lengths of the 1/4" tubing are equal. This ensures that each tube length between the controller and each injection valves will have equal volumes. Since some valves will be closer to the controller, there will be extra tubing between the controller and the valves. The extra tubing should be coiled and tied out of the way.

The HT-3 has a three position selector switch, one position for each tank, located in the upper right hand corner of the control panel face plate. All other controls on the panel are common and set perameters that are shared by each tank. Because the injection time, injection pressure and dwell controls are common, adjustments may be necessary if the tanks vary in size or shape or liquid level. There are six instead of two outlet ports (HT-1 has two and HT-2 has four) on the controller for the injection valves.

When the HT-3 is equipped with the RC option, it is installed in a larger enclosure (12"x14"instead of 10"x12") because solenoid valves are added, requiring extra room for plumbing.