TL Series — HMI Controls & Operation (TL-450 Plus, TL-1050 Plus, TL-1825 & TL-1725) – South-Tek Systems

Applies to: N2-GEN Arc Suppression — TL Series · TL-450-Plus · TL-1050-Plus · TL-1825 · TL-1725 (touchscreen HMI)

This article covers the touchscreen HMI used on the Plus, TL-1825, and TL-1725 units. If your unit has a PLC with a Run/Standby display, see the legacy System Operation article instead. Controls for supporting equipment such as the compressor and dryer are not covered here; refer to those manufacturers' instructions.

▲ Attention The control program is proprietary and password-protected from the factory. Do not alter controls, calibration, or setpoints without approval from South-Tek Systems. Unauthorized changes void the warranty and the unit's performance specifications.

Home screen

The home screen shows system status, the purity set-point, nitrogen storage tank pressure and purity (if the sensor option is included), and run hours. From here you can start or stop the unit and open the Menu, Graph, or Alarms screens.

Powering on and off

Power the unit on and off with the external power switch or external disconnect (typically supplied by others).

Starting and stopping

Start and stop the generator with the Start/Stop button in the upper-left corner of the touchscreen. Green means the unit is started (On); red means it is stopped (Off). Press the button to switch states.

When running, the unit automatically cycles the adsorption beds to fill the storage tank. At the cut-out pressure it enters Standby and pauses production; when the tank falls to the cut-in pressure it restarts automatically.
When stopped, all valves return to their normal position. Valve off the nitrogen storage tank outlet to the process so tank pressure does not fall below the cut-in pressure. Losing tank pressure can briefly put purity out of specification when the unit restarts.

System run hours

Run hours appear in the upper-right corner of the home screen, below the time and date. They count only while the system is cycling and producing nitrogen; standby time is not included.

Trending graphs

The Graph button on the home screen opens historical trending data for the unit's sensors. Every unit trends nitrogen storage pressure. Optional traces include oxygen purity, air flow, nitrogen flow, and incoming air pressure.

Adjust the Y-axis scale by entering min and max values in the lower-left corner. Press a box, enter the value on the keypad, and press enter; the graph rescales automatically.
Toggle the M button to scroll back through the graph memory with the « and » buttons. Toggle the G button for horizontal gridlines. Use Next to move to the next graph or Exit to return home.

Menu screen

The Main Menu is password-protected. The user password is on the Revision History page of the hard-copy manual supplied with the unit. From the menu you can reach Sensor Setup/Calibration, Maintenance Menu, Alarms/Filter Parameters, Communication Settings, and Cut-in/Cut-out Parameters. Factory Settings is locked.

Alarms and filter parameters

The Alarms/Filter Parameters screen shows the O2 and low-pressure alarm setpoints next to their current values.

The O2 alarm trips when the current oxygen reading rises above the %O2 High Level (or O2 PPM Max) setpoint.
The Low N2 Tank Press alarm trips when the tank pressure falls below its setpoint.
Alarms and the local audible can be enabled or disabled on the Other Settings screen. If the unit includes the Low Purity System Purge option, it is also enabled there, with a delay time and warmup period.
The red Alarms button opens the Alarm Status screen, where Filters Info, Alarm Details, Alarm History, and Clear History are available. Alarm Details lists each alarm with the time and date it triggered.

Alarm Setup screen with O2 and low-pressure setpoints

Pressure cut-in / cut-out

A pressure transducer measures storage tank pressure and sets the cut-in and cut-out points. At cut-out the unit enters Standby and stops producing nitrogen; at cut-in it resumes. View the factory setpoints under Menu → Cut-in/Cut-out Parameters.

Note: The cut-in and cut-out settings are factory set. Do not adjust them without contacting South-Tek Systems, as this can alter nitrogen purity and flow capability.

Maintenance menu

The Maintenance Menu lets you toggle each valve individually to confirm it is working. Put the unit in the Stopped state and close the nitrogen outlet valve before toggling valves, and reset all valves to Off before restarting the system.

Information screen

The Information screen shows run hours, software version, manufacture build date, serial number, and commission date, with a shortcut to filter history.

Sensor calibration

The Sensor Setup/Calibration screen calibrates the unit's sensors. Every unit has a nitrogen storage pressure sensor; an oxygen sensor is a common add-on, and other temperature, pressure, flow, and dew-point sensors are available. All sensors use a 2-point linear calibration from two known points at opposite ends of the range. Enter the Low and High Limit Raw values from the current raw reading while each known source is applied.

Sensor	Low Point	High Point
Pressure	0–5 PSIG	100–150 PSIG
O2 %	0.5–1.5% O2	10–21% O2
O2 PPM	100 PPM	1000 PPM

When calibrating an oxygen sensor, use certified gas for the low point and clean dry compressed air (20.9%) for the high point, flow only 1 to 2 scfh to the sensor to avoid damage, and never block the sensor's purge line. Because calibration affects measured purity, perform it with South-Tek Systems guidance.

Optional features

Availability depends on how your unit was ordered. Configuration of these features is done with South-Tek Systems support.

Data logging: collects system data (pressure, flows, O2, temperature) into current/average/max/min readouts and can write a .CSV file to a South-Tek formatted micro SD card in the controller. Use the Start, Stop, and Reset Stats controls on the Data Logging screen.
Ethernet communication: with the optional Ethernet card, assign a static IP to the controller for Remote Access, SD Card Access, and Modbus TCP/IP. A connection status message confirms the link.
EverPure (TL-1725): a smart auto-purge feature that holds the storage tank at or above design purity during long idle or low-flow periods, using an Extended Standby timer in the Pressure Settings menu.
Duplex (TL-1725): integrates a paired unit for added capacity or backup, configured from the Pressure Settings menu.
Staging (TL-1725): integrates two generators into an alternating, redundant system. It balances run time, switches the primary unit after 1,000 hours by default, and avoids downtime during scheduled maintenance or a single-unit failure.
Oxygen analyzer (7100): verifies storage-tank purity and can be synced to the generator display during O2 calibration.

Need help? South-Tek Systems Service — Phone: (910) 415-1880 · Open a support ticket at support@southteksystems911.zendesk.com or through the Help Center.