Card Types

Question 1

NAI

Answer 1

Annunciator Interface Card

Provides an interface between the Low Voltage systems (ie: Signal Comparator cards, NAL) and the High Voltage Systems (ie: Annunciator System).

Question 2

NAL

Answer 2

Signal Comparator Card

The NAL card function is to recieve up to two differential input signals, compare thier sum with an internally generated setpoint, based upon the result of the at comparision provide a current sinking or current blocking output signal.

NAL G01
Is referred to as a “SINGLE” comparator in that it can recieve one set of two differential input voltages, sum them, compare them to an internal setpoint and generate a single output.

NAL G02
Is referred to as a “DUAL” comparator. It operates similarly to the group 1, except that the single set of two differential inputs once summed together are distributed to be compared to two separate independent setpoints and produce two independent outputs. Each of the comparison and outputs may be completely different action than the other.

NAL G03
Is referred to as a “DOUBLE” comparator. It operates as if it were two group 1 circuits housed on a single board (different: inputs, setpoints, & outputs; completely separate). The ONLY thing shared are some power supply circuits.

NAL G07
The “New Generation” NAL card, was created becasue of parts obsolescence issues. The power supply circuits have been updated and optical isolation was added to the outputs. The G07 card can be jumper configured to operate as a G01, G02, or G03 card.

Question 3

NAS

Answer 3

Auxillary Solid State Relay card

Provides an interface between the Low Voltage DC of the NAL card and High Voltage AC external circuits. (typically the High Voltage AC circuits are 120VAC relay coils)

***NAS cards are all located in cardframe #9 (because it has High Voltage).

Question 4

NCH

Answer 4

Function Generator card

Takes the input signal voltage and “Characterizes”/shapes it to meet the requirements of the process loop, it is then output to the process loop.

notes: “ The NCH card generates a characterized/shaped output function from the linear input signal voltage.” It will accept a Bi-polar input.

Question 5

NCI

Answer 5

Computer Interface card

The NCI card exists to provide a measure of isolation between a PROTECTION Loop and the Plant Computer (IPC).

***notes: two 15K Ohm resistors

Question 6

NLL

Answer 6

Lead / Lag card

Question 7

NLP

Answer 7

Isolator and Loop Power Supply card

Question 8

NMA

Answer 8

Analog Mixing Amplifier card

The function of the NMA card is to provide general purpose analog computing functions of Addition, Subtraction, Signal Selection (High or Low), Gain, Lag, Integration, Differentiation, & Output Limiting.

Question 9

NMD

Answer 9

Multiplier Divider card

Math functions that can be performed by card:
AxB
A/C
(AxB)/C
√(A) or √(B)
√(AxB)

√(% ΔPressure) = (% Flow)
The formula above will not work with actual values (Ie: voltages), percentages must be used.

Example: When ΔPressure = 75% what is the % Flow?
Answer:
% Flow = √(0.75) = 0.866025
0.866025 = 86.6025%
86.6025% of the 0-10V scaled value = 8.660 VDC

• *note1: √(…) = square root symbol
• *note2: √(…) function, “Input C” will always have a gain of 0.2

Question 10

NPC

Answer 10

Potentiometer card

THe NPC card performs voltage division of analog input signals for loop scaling purposes.

Inputs are 0-10 VDC.

Question 11

NSC

Answer 11

Signal Converter card

Converts signals from one range to another (1-5VDC to 0-10VDC). On-board 100Ω & 250Ω resistors are provided for 10-50mA & 4-20mA loops, respectively (G03 & G07 cards only).

Any jack labeled 1-5VDC output will actually read negative 1-5VDC between it and signal common.

Question 12

NVP

Answer 12

Voltage to Pulse Converter card

Question 13

NSA

Answer 13

Summing Amplifier card

Module Equation:
Eo = [(EaGa)+(EbGb)+(EcGc)+(EdGd)+(EbiasGbias)]Ggain

Find Bias first, then find the gain.

Question 14

NRS

Answer 14

Rod Speed card

Rod Control Supply Voltage = -9.5 V
Shutdown Speed to BSS = -8.57 V, 64 steps/min
Control Speed to BSS = -6.763 V, ??? steps/min

RC –> Rod Control
BSS –> Bank Selector Switch
1 step = 5/8 inch

“Rods out contact to rod control” is not used anymore.

Question 15

NVP

Answer 15

Voltage to Pulse Convertercard

Produces a pulse rate proportional to the magnitude of the input voltage.

Question 16

NQP

Answer 16

Quad Loop Power Supply card

“Enable” must be connnected to ground for hte card outputs to work.

100mA fuses on each loop, provides the “semi-isolation”.

Optional 252.2Ω resistors are connected to each loop to measure the 4-20mA signal on a 1-5VDC reading.

Question 17

NTJ

Answer 17

Test Jack card

Provides 10KΩ isolated points into the system for monitoring.

If an accidental connection is made, very limited current will be allowed to flow. (10V/10KΩ = 0.001A)

Question 18

NTP

Answer 18

Test Point Card

Provides the ability to connect 4-20mA and/or 0-10VDC signals for monitoring. A 250 resistor is supplied to monitor the 4-20mA signal as 1-5VDC.

Question 19

NCB

Answer 19

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