NOVUS N1200 User Manual

NOVUS Sensors

RUA ÁLVARO CHAVES, 155

TEL: (51) 3323.3600

PORTO ALEGRE - RS - BRAZIL

FAX: (51) 33233644

90220-040

e-mail:[email protected]

5001062

Using the HBD option for the N1200 controller

Heater Resistance Fail Detector

The HBD (Heater Break Detector) option provides means of
detecting a mal function in the heater resistance, by monitoring the
current that flows through it. This option consists of a dedicated PCB
connected internally to the N1200 and a current transformer (CT)
mounted externally at the load.

Installation

When the HBD model controller is ordered, the HBD accessory is
already mounted in the N1200. The user must then connect the CT
to terminals 14 and 15 at the instrument back panel (any polarity).

The CT was designed such as to facilitate its insertion in the load
circuit. The CT core can be opened to allow the load wire to be
installed inside the core, without opening the circuit. The CT wires
may be stretched up to 3 meters long and must be kept away from
other wires and cables of the installation.

Operation

When the PWM control output is used, the controller monitors the
load current when this output is turned ON and OFF, indicting on the
kb.i

kb.i

kb.i screen the current with higher value (usually, the current that is
present when the output is ON.)

The minimum current alarm (Kb.L

Kb.L

Kb.L) takes this ON current

measurement and compares it with the respective setpont value. If
this current is below the alarm set point, the alarm is activated,
indicating a faulty resistance.

The maximum current (Kb.k

Kb.k

Kb.k) alarm compares OFF current

measurement with the setpoint for this alarm. If the current is above
the alarm set point, the alarm is activate to indicate problems in the
actuator (short-circuited SSR, bad contactor , etc.).

The minimum/maximum current alarm (Kb

Kb.Lk

.Lk

.Lk) executes both

operations described above simultaneously.

Controller configuration

The HBD parameters are:

Parameter

Function

Cycle

kb.i

Current indication as measured by the
CT (in amperes)

Operation

Cycle

kb.fs

Maximum CT Span.

For

the

accompanying the

controller, this parameter must be
defined as 60.0, an indication that the
maximum measured current is 60 A

Scale Cycle

In the alarm Functions parameters, the parameters are:

Parameter

Function

Cycle

Fua1

Fua2

Fua3

Fua4

Kb.L

Kb.L Minimum current alarm.

Kb.k

Maximum current alarm.

Kb.Lk

Minimum

and

maximum

current alarm.

Alarm cycle

When a HBD alarm functions is used, its alarm setpoint is
expressed in Amperes..

Parameter

Function

Cycle

SP.A1

SP.A2

SP.A3

SP.A4

Electric current values in amperes (A)

Tuning cycle

Notes:

1- For a perfect operation of the controller in monitoring the electric
current, the PWM Cycle Time (

cccctttt) must be defined with a value

above 2 seconds.

2- Between terminals 13 and 15 of the controller, its feature I/03 is
available with all its functionalities.

3- The current measure accuracy is 3.3% (±2A).

For any other situation that does not use the PWM control output,
the display current value is the instant value measured.