M4557 - Model 9210 Nitriding Controller
SSi Manual SERIES 9210-M4557-Nitriding Page 10 of 10
software installed. The Micrologix 1200 is used in conjunction with the 9210 for alarm and event handling
purposes. The Hi-Limit controller provides furnace over-temperature protection. The UPS Unit provides
Battery backup and surge protection for the 120Vac that is used to power the 9210’s 24Vdc power supply
and the Micrologix PLC .
The UPS will provide up to 15 minutes of power in case of power loss. To properly shutdown the Nitriding
panel …SHUTDOWN the ADVANTECH screen (see instructions), then open panel door and turn OFF UPS.
The panel is now safe for electrical work.
There are NO implied safety devices included with this control system.
The safety system (atmosphere flow and pressure) is the responsibility of the customer.
Stand-alone Flow Panel includes the atmosphere flow sample enclosure, the flow switches, back-
pressure control (if part of the system), the flow control devices, and the pressure switches. The Flow
panel is interconnected with the Control panel to allow the Nitriding Control system to provide control of
Gas flows, the furnace’s back-pressure and monitoring of supply and exhaust pressures for alarming. The
flow panel is designed to supply up to four different gases to the furnaces. Typical gases used are
Nitrogen, Ammonia, Dissociated Ammonia and Hydrogen.
Nitriding Control System: Mode of Operation -
A typical 9210 Nitriding Control system allows the user to automatically run the Nitriding cycle without
requiring operator intervention. The system will set temperature, % Dissociation/Kn, Back Pressure and
Gas Flows as part of it’s recipe. To control the % Dissociation/Kn, the 9210 has the ability to adjust the
Gas flows at any step of the process. Typically, the Ammonia flow rate is adjusted to achieve the desired
% Dissociation/Kn. This adjustment uses the Trim Enable and Trim Range variables. These variables can
be set by the recipe or manually from the Detail screen. Trim Enable determines whether the Gas flow can
be adjusted. Trim Range is a +/- band from setpoint that the Gas Flow setpoint can be adjusted to. For
example, Ammonia Flow Setpoint = 50,Ammonia Trim Enable = Yes and Trim Range = 20. With these
settings the Ammonia Flow setpoint can be adjusted from 30 up to 70. The amount of adjustment is
determined by the % Dissociation/Kn control loop. If the % Dissociation/Kn requires more ammonia the
setpoint is increased, if less ammonia is required, the ammonia flow setpoint is decreased.