Detcon 812B User Manual

detcon inc.

Detcon

Model 812B

Rack Mount Control Enclosure

Operator’s Installation & Instruction Manual

March 1, 1999 Document #2079 Ver. 1.1

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

ALARM 3

ALARM 2

ALARM 1

FAULT

ALARM
RESET/

Test

HOUSTON, TEXAS

detcon inc .

able

disable

ALARM

MODEL 12B

HYDROGEN

SULFIDE

MONITOR
ppm H2S

HOUSTON, TEXAS

detcon inc.

POWER

ON/OFF

FUSE

2 AMP

Model

PS80-12B

FUSE

PRESS

M

odel

812B

HOUSTON, TEXAS

detcon inc.

Table of Contents

1.0 Introduction

1.1 Description

1.2 Specifications

1.3 Schematics

1.4 Installation

1.5 Start-up

1.6 Maintenance & Repair

1.7 Spare Parts List

1.8 Warranty

1.0 INTRODUCTION

Detcon Model 812B consists of 3 major assemblies:

1. The NEMA 1 rack mount control enclosure.

2. The single channel digital control modules.

3. The remote mount gas sensor assemblies.

The NEMA 1 control enclosure is detailed in section 1.0 of the manual, the control modules in section, 2.0 and
applicable sensor assemblies in section 3.0.

1.1 D

ESCRIPTION

Detcon Model 812B rack mount control enclosure, along with Model 12B digital control modules, is designed to
serve as a host assembly for up to eight remote mount gas detection sensor assemblies. The control enclosure is
rated NEMA 1 suitable for installation in non-hazardous locations.

The single channel modular design supports application f lexibility wherein multiple function gas detection systems
can be configured in any combination up to eight channels. All control modules are plug-in front panel accessible
for easy maintenance and repair. The system is powered by VAC line power and/or 24VDC unless otherwise speci­fied at time of order.

The control enclosure houses a modular power supply (Model PS80-12B) which includes, as standard operating con­trols, a power on/off switch and a line power fuse. Discreet output terminal strips located on the controller mother­board are provided for sensor terminations, Form C dry contact alarm outputs for three alarms plus fault (common
and choice of normally open or normally closed), 4-20 mA outputs for remote recording devices, and RS-485 serial
Modbus™ output. Additional terminations are provided for VAC power in, VDC power in, and remote alarm reset.

The Form C relay outputs, may be discreet, zoned, or common by gold plated jumper tabs located on the con­troller mother board.

1.2 SPECIFICATIONS

Electrical Classification

NEMA 1

Dimensions

19''W x 7''H x 8.75''D

Capacity

8 single channels

Power Input

117VAC/24VDC

PPoowweerr CCoonnssuummppttiioonn

5 watts per channel (full alarm peak load)

Model 812B Rack Mount Control Enclosure PG.2

Model 812B Rack Mount Control Enclosure PG.3

OOuuttppuuttss

Discrete Analog 4-20 mA DC
Serial RS-485 Modbus™

AAllaarrmm RReellaayyss

(discrete or zoned)

Contacts include common with jumper selectable choice (on controller) of normally-open or normally-closed for four alarms

Resistive load: 5A, 250 VAC; 5A, 30 VDC
Inductive load: 2A, 250 VAC; 2A, 30 VDC
Max. operating current: 5A

OOppeerraattiinngg TTeemmppeerraattuurree RRaannggee

-40°F to +175°F

WWaarrrraannttyy

One year

1.3 SCHEMATICS

A

B

C

D

E

F

H

J

K

L

M

N

P

R

S

T

U

V

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

mA

Sensor

NO/NC

Com

Alm 3

NO/NC

Com

Alm 2

NO/NC

Com

Alm 1

NO/NC

Com

Fault

4-20mA

Out

Typical

Connector

x 8

Typical

Jumpers

x 7

CH8 CH7

P8 thru P1

Typ. x 8

Alarm

Reset

P9

L1

N

A (+)

B (–)

Shld

RS-485 VDC In

GND

VAC In

P10

P11

P12

P13

812B

Motherboard

Schematic

L1

N

GND

+ In

– In

+ Out

– Out

1.4 INSTALLATION

1. Securely mount the 812B enclosure in accordance with the drawing in figure 1.

NNoottee::

Reference figure 2 for wiring terminations.

2. Connect 117VAC input to the terminal strip labeled “VAC IN” (L1, N, GND).

3. If applicable, connect a 24VDC source or standby battery to the terminal strip labeled “VDC IN” (+ and –).

4. Refer to installation and wiring detail of remote mount sensor assemblies as detailed in section 3.0. Terminate
field wiring from sensors to the 812B motherboard. Terminals are labeled “SENSOR” (MA, + and —).

5. If applicable, terminate the discrete 4-20 mA outputs to external device(s). Terminals are labeled “4-20 mA OUT”
(+ and —).

6. If applicable, terminate the RS-485 serial output to external device(s). Terminals are labeled “RS-485” (A+, B–,
and Shield).

Model 812B Rack Mount Control Enclosure PG.4

PS80-12B Power Supply Schematic/Wiring Diagram

BLK

RED

Power
Supply
DC Out

P2

Power

Switch

P3

16ga x 6"

16ga x 6"

BLK 16ga x 9"

BLK 16ga x 9"

TAN 22ga x 9"

TAN 22ga x 9"

RED 16ga x 9"

RED 16ga x 9"

TB2

Pin 5 Com

Pin 7 +

Power Supply

Pin 1

Pin 2 N

Pin 3 L

D1 6A 50V

TB1

D2 6A 50V

16ga x 6"

16ga x 6"

16ga x 6"

Power
Supply
VAC In

GND - GRN

N - WHT

L1 - BLK

P1

L1 In
N In
GND In
+DC In
–DC In
+DC Out
–DC Out

P5

Fuse

P4

16ga x 9"

BLK

BLK 16ga x 9"

7. Based on the application and use of relay contact outputs, complete all wiring terminations prior to application
of power. Shut-in controls may be omitted until system test is complete. Terminals are labeled “ALARM 1”,
“ALARM 2”, “ALARM 3”, and “FAULT” (COM & NO/NC). Relay contact outputs may be discreet or zoned
via the gold-plated jumper tabs.

8. If applicable, terminate a remote mounted normally open momentary switch to the terminations labeled “Alarm
Reset”. Activation of the alarm reset function will reset the alarms of all Model 12B controllers. The reset func­tion is effective when the Model 12B’s respective alarms have been programmed in the latching position and
alarm conditions have passed. Each Model 12B controller has its own alarm reset switch which is discussed fur­ther in section 2.0.

Model 812B Rack Mount Control Enclosure PG.5

Alarm

Reset

L1

N

A (+)

B (–)

Shld

RS-485 VDC In

GND

VAC In

Zone Programming Jumpers

mA

Sensor

NO/NC

Com

Alm 3

NO/NC

Com

Alm 2

NO/NC

Com

Alm 1

NO/NC

Com

Fault

4-20mA

Out

CH8 CH7 CH1

Figure 2

Figure 1

Panel cutout (centered) 17.5 x 6.65

Panel depth - 8.75

3

7

.375

.218

Slot Detail
use 10-32 screw

19

1.5 START UP

Upon completion of all field wiring: Depress the power switch located on the front panel. Note that each Model
12B controller digital display illuminates. Varying readings may occur during sensor warm-up. A 10 second alarm
delay will occur on power up. Refer to section 3.0 for additional sensor start-up detail.

1.6 MAINTENANCE & R

EPAIR

The Detcon Model 812B’s modular design allows for minimum down time during maintenance and/or repair. A
model 12B control module may be changed by simply loosening its mounting screw and sliding the module out of
its card cage. See section 3.0 for more information on the 12B control module.

The Model PS80-12B 80 watt power supply can be replaced by first loosening its two mounting screws and then
sliding it out of the panel. A new power supply can then be installed or the existing one repaired. It is recommend­ed that VAC and VDC power be removed from the 812B motherboard before doing maintenance on, or replacing
the power supply.

Replacement of the power switch, or fuse holder is accomplished by: removing the power supply from the panel;
disconnecting the plug from its respective header; remove the wires from the plug of the component to be replaced;
snap the component out of the PS80-12B face plate and then reassembly with the new component. Reference the
PS80-12B schematic/wiring diagram in section 1.3 for wiring details.

Replacement of the power supply itself is accomplished by: removing the PS80-12B power supply module from the
panel; disconnecting the four plugs from their respective headers; removing the 3 screws that secure the PS80-12B
face plate to its bracket; removing the 4 screws that mount the power supply to the bracket; disconnect the wires
from the power supply and then reassembly with the new power supply. Reference the PS80-12B schematic/wiring
diagram in section 1.3 for wiring details.

1.7 SPARE PARTS LIST

Par

t # Description
0224 Gold plated jumper tab
951-5880-121 PS80-12B 80 watt modular power supply (this is the complete plug-in power supply module)
360-801024 80 watt, 24 VDC switcher power supply (replacement power supply for PS80-12B)
2812 24 VDC lamp for power switch
0298 2 amp 3AG slow blow fuse
320-3217-1 Power switch assembly
2806 Green switch cap (for power switch)
3280 Fuse holder

1.8 WARRANTY

Detcon Inc., as manufacturer, warrants under intended normal use each new Model 812B rack mount control
enclosure to be free from defects in material and workmanship for a period of one year. The warranty period begins
from the date of shipment to the original purchaser and ends one year thereafter. All warranties and service policies
are FOB the Detcon Inc. facility located in The Woodlands, Texas.

Model 812B Rack Mount Control Enclosure PG.6

Shipping Address: 3200 A-1 Research Forest Dr., The Woodlands, Texas 7381

Mailing Address: P.O. Box 8067, The Woodlands, Texas 77387-8067

phone [phone] • fax [phone] • www.detcon.com • [e-mail]