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Option 32.0 - Trim limit default (0/1) LV3

0 = Default Trim Limit of

5%

1 = Enables options 32.1 to 32.4

Options 32.1 to 32.4 - Trim limits (0.0 – 25.0) LV3

Option 32.0 is only available if option 30.5 (oxygen input function) has been set for closed loop oxygen

trim.
It is possible for the system to trim the air or fuel drives up to a maximum deviation of ±25.0% of the total
air or fuel flow for the chosen trim drives.

If option 32.0 is set to 0, the default trim limit will be ± 5.0% for all profile selections. Option parameters
32.1 to 32.4 will not be available.

If option 32.0 is set to 1, it is possible to individually adjust the trim limit for each profile selection using
option parameters 32.1 to 32.4.  The trim limit may be adjusted from 0.0% (no trim) up to a maximum of ±
25.0% (maximum allowable trim).

It is the responsibility of the commissioning engineer to ensure the trim limit set will not allow a
hazardous combustion condition to occur in the event of an oxygen probe failure. Where oxygen
is to be considered safety critical, option parameters 31.X should be used to setup a second
oxygen monitor. When a second oxygen monitoring system is used, the oxygen can be
considered fail-safe, and the trim limits can be set up to 50% instead of 25%.

Options 33.1 to 33.4 - Trim integral gain (Default 10%) LV3

Options 33.1 to 33.4 are only available if option 30.5 (oxygen input function) has been set for closed loop
oxygen trim.

In order for the oxygen trim control loop to be stable, the integral gain must be set correctly.  Options 33.1
to 33.4 allow the integral gain to be set individually for each profile combination to any value between 0.0
and 99.9%.  As a general recommendation, the integral gain should be initially set to 10.0%. This value
must be set above 0.0 for the system to apply trim.

If the burner is firing, it is only possible to make an adjustment to the option parameter that relates to the
selected profile.  If the burner is not firing, the integral gain for any profile selection may be adjusted.

Option 34.0 - Trim proportional gain (0/1) LV3

Options 34.1 to 34.4 - Trim proportional gain (0.0 – 99.9%) LV3

Options 34.0 to 34.4 are only available if option 30.5 (oxygen input function) has been set for closed loop
oxygen trim.

If oxygen trim proportional gain is not required for any profile selection, set option parameter 34.0 to

0

.

If oxygen trim proportional gain is required, set option parameter 34.0 to

1

.  Option parameters 34.1 to

34.4 will then become available.  Options 34.1 to 34.4 allow the loop gain to be set individually for each
profile selection to any value between 0.0 and 99.9%.

Oxygen trim proportional gain is not normally required.

O 2

O 2

O 2

Summary of Contents for NEXUS NX6100 series

Page 1: ...1 of 27 Type2 Oxygen probe system for Nexus NX6100 and PPC6000 Supplement to NEX6101 PPC6001 NXPK2244 July 24 2019...

Page 2: ...Connection of Line voltages to the NXO2TRIM will damage the product beyond repair The interconnection system between the NXO2TRIM and the NXPK224455 56 57probes is considerably different to the wiring...

Page 3: ...3 of 27...

Page 4: ...4 of 27...

Page 5: ...mum cable length limitations Cabinet designers MUST ensure that Line voltage and Extra Low Voltage ELV cables are segregated within the burner cabinet distribution panels and conduits The manufacturer...

Page 6: ...series controller must be to the CANbus 4 core screen cable specification in the main product manual NEX 6101 or PPC 6001 Connect the CAN cable braid screen at the controller using the screen terminat...

Page 7: ...4 20mA Input 3 0 5V PG9 O2 Trim Interface GND 4 20mA Input 0V 0V PH1 O2 Trim Interface Probe 1 Black 0 14V PH2 O2 Trim Interface Probe 2 Red 0 14V PH3 O2 Trim Interface Probe 3 Yellow 0 14V PH4 O2 Tri...

Page 8: ...es on this face Probe connection terminals PH1 to PH8 CAN and 4 20mA connection terminals PG1 to PG8 Ring terminal point for screen termination Internal view of NXO2TRIM Do not Connect 120Vac NXO2TRIM...

Page 9: ...27 Calibration port Removable terminal block NOTE There is no screen termination point The screen in the 6 way cable must be cut short to the PVC outer cover View of NXPK224455 56 57 oxygen probe term...

Page 10: ...SAFE AFTER COMPLETION Additionally the oxygen probe calibration should be checked before and after the procedure since the results depend highly upon measurements taken using the probe Before proceed...

Page 11: ...hown on the display use the scroll keys to position the pointing to the O2 value use the UP DOWN keys to adjust the oxygen setpoint as necessary The display will start flashing to indicate that a chan...

Page 12: ...ption 30 1 Oxygen probe calibration offset value 0 999 LV3 This option parameter is only available if option 30 0 is non zero This option parameter must be set to the calibration offset value that is...

Page 13: ...below Option parameter 30 5 value Meaning 0 Monitor only The oxygen value is only used to provide a display of the measured oxygen level 1 Closed loop trim The oxygen value is used to provide both a d...

Page 14: ...e burner modulates Only the trim profile is affected The Oxygen set points and flow values are not changed This option parameter allows the learned trim profile to be reset If the option is set to 1 a...

Page 15: ...MODE TO MANUALLY CHECK THE CALCULATED FLOW VALUES OXYGEN SETPOINTS AND TRANSPORT DELAY THE LOW FIRE PERCENTAGE FLOW VALUE SHOULD CONFORM APPROXIMATELY TO THE TURN DOWN RATIO OF THE BURNER SUMMARY To p...

Page 16: ...the trimmed drives will still be attained Option parameter 31 0 value Meaning 0 Modulation not limited Burner modulates from P3 to Ph Oxygen trim works over full range from P3 to Ph but may not be ab...

Page 17: ...instead of 25 Options 33 1 to 33 4 Trim integral gain Default 10 LV3 Options 33 1 to 33 4 are only available if option 30 5 oxygen input function has been set for closed loop oxygen trim In order for...

Page 18: ...ess enter 7 Wait until the oxygen reading has stabilized then record the excess air value at location b1 in the table relating to the current profile position 8 Repeat the above for all other profile...

Page 19: ...b3 c3 d3 e3 c3 d3 f3 e3 f2 g3 f3 y c3 4 A a4 b4 c4 d4 e4 c4 d4 f4 e4 f3 g4 f4 y c4 5 A a5 b5 c5 d5 e5 c5 d5 f5 e5 f4 g5 f5 y c5 6 A a6 b6 c6 d6 e6 c6 d6 f6 e6 f5 g6 f6 y c6 7 A a7 b7 c7 d7 e7 c7 d7 f7...

Page 20: ...an upward direction will scroll through all temperature sensor options available until 0 nothing is displayed Enter this value to disconnect the specified device from any hardware Scrolling the list i...

Page 21: ...fuels These values should be used as a guide only If the display is required to show gross efficiency in addition to entering the gross calorific values a non zero value for the boiler radiated heat l...

Page 22: ...to the option parameter that relates to the selected profile If the burner is not firing the high alarm value for any profile selection may be adjusted When the flue temperature rises above the high a...

Page 23: ...value entered relates to a percentage deviation from each oxygen set point in the firing range If the burner is firing it is only possible to make an adjustment to the option parameters that relate to...

Page 24: ...ault codes There is one change that will be observed in the EK data The EK72 value Oxygen Probe Cell Temperature will be higher for the NXPK224455 56 57 oxygen probe The normal value will be 820 C 1 5...

Page 25: ...gen sensor heater supply Oxygen sensor temperature set point Oxygen measurement accuracy Auxiliary Inputs Type Input impedance Pre assignment Flue gas temperature input Type Measurement range Flue tem...

Page 26: ...r replacement pressure Unit Weight 0 to 70 C 0 to 158 F IP20 600 C 1 112 F Zirconia oxide cell 1 21 Oxygen 5s Less than 15s for 63 change Type K thermocouple Ambient air at 20 9 O2 3 O2 in Nitrogen 35...

Page 27: ...ich is found defective in material or workmanship or which otherwise fails to conform to the description of the product on the face of its sales order THE FOREGOING IS IN LIEU OF ALL OTHER WARRANTIES...

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