CaptiveAire R850 User Manual

Innovative Control Solutions For Your Needs

R850 SERIES

R850V STEP CONTROLLER

WITH INTEGRATED VERNIER STAGE

• Pulsed or analog 0 to 10 Vdc vernier stage

• 4 or 8 step models

• Up to 16 stage total with a slave unit

• Test button

DESCRIPTION

The Viconics R850V series step controller is designed for
cost effective, precise modulation of multi-stage control
application. A common application is a multi step electric
duct heater.

An integrated vernier control output will give a precise and
full modulation of the load from 0 to 100% of the total
capacity.

FEATURES AND BENEFITS

Microcomputer-based design Accuracy and reliability
Adjustable inter-stage delay Provides flexibility in

replacement applications

Adjustable Vernier ratio Simplifies design of

proportional stage
Choice of pulsed or analog
Vernier output

Permits use of SCR or lower

cost SSR
Up to 16 stages One product family can handle

all applications
Choice of LIFO or FIFO
sequencing

Increased flexibility of FIFO

permits even use of contactors
Test button Quick troubleshooting

MODELS AVAILABLE

The R850-V is available in 2 models

• R850V-4 4 stage unit

• R850V-8 8 stage unit

If more than 8 stage are required, the R850-V8 can be used

OVERRIDE TEST BUTTON

The override test button can be used to by-pass the
interstage delay and bring on all stage at one time. This
simplifies the verification of configured maximum number of
stage.

A status LED per step will come on for each of the configured
stage.

SPECIFICATIONS

Operating

Conditions:

0°C to 80°C ( 32°F to 176°F )
0 % to 95 % R.H. non-condensing

Relay outputs: Isolated relay 30 Vac @ 1.0 amps. max. per

output, up to a maximum of 4.0 amps. total
per R850 controller. See application note 02.

Vernier stage: Vdc pulsed: 6 Vdc, 30 mA max.

0 to 10 Vdc 5 mA max.

Input

0 to 10 Vdc into 10 KΩ minimum

impedance:

Power supply: 24 Vac -15%, +10% 50/60 Hz; 4 VA

Use a Class 1 ( properly fused ) or Class 2,
CSA or UL recognized transformer for power
supply & relay outputs.

Specifications and equipment are subject to change without prior notice.

as a master unit with another R850V as a slave unit. Adding
another unit ( R850-V4 or R850-V8 ) can bring the total step
number up to 12 or 16.

INPUT SIGNAL

The R850V has four INPUT dip switch (S1 to S4) to select the control signal input:
They are compatible with industry standard signals.

DIP SWITCH ADJUSTMENTS & WIRING CONTROL INPUT

ON

INPUT DIP SWITCH à ß CONTROL DIP SWITCH

(1-4) Input signal selection

0 to 10 Vac

4 to 20 mA
0 to 135 Ω

ON

21 3 4

21ON4

ON

21 3 4

1

2 3 4 5 6321 4

I

P

N

U

3

ON

SW1

T

C

SW2

L

T

R

N

O

O

(3-6) Number of steps selection

(see next pages for details)

(2) Vernier stage selection

OFF = 0 to 10 Vdc (SCR)
ON = Vdc pulsed signal (SSR)

(1) Sequence of operation (LIFO or FIFO)

OFF = LIFO (Last IN, First OUT)
ON = FIFO (First IN, First OUT)

Input Signal Switch Switch #1 Switch #2 Switch #3 Switch #4

0 to 10 Vdc control signal ( 2 to 10 Vdc control range ) Off Off Off On
4 to 20 mA control signal Off Off On Off
0 to 135 Ω control signal

On On Off Off

If a slave unit is used, wire the control signal input to the master unit only

2 To 10 Vdc Or 0 To 10 Vdc Stand Alone Thermostat

10 Vdc = 100% capacity

135 Ohms = 100% capacity

10 Vdc = 100% capacity

20 mA = 100% capacity

( Power To The Thermostat Is Supplied By The R850V )

0 To 135ΩΩ Stand Alone Thermostat

1

1 2 3ON4

I

N

T

P

U

2 Vdc = 0% capacity

Common

24 Vac

0 to 10 Vdc

output

123

2 To 10 Vdc Or 0 To 10 Vdc From D.D.C.

Building Automation System

1

1 2 3ON4

123

I

PUT

N

2 Vdc = 0% capacity

-

+

0 Ohms = 0% capacity

Building Automation System

4 mA = 0% capacity

1

1 2 3ON4

123

W

R

B

I

4 To 20 mA From D.D.C.

1

1 2 3ON4

123

­+

PUT

N

I

T

P

U

N

24 VAC POWER & RELAY OUTPUT WIRING

The wiring diagrams are for the R850V-8 models with 8 outputs. The wiring for the R850V-4 is the same except that the unit only
has 4 outputs.

Terminals

Screw terminal & connector #1 Common
Screw terminal & connector #2 24 Vac
Screw terminal & connector #3 Control Signal input

• It is not necessary to ground any leg of the transformer to earth with the controller card.

• The controller uses internally a half wave rectifier bridge. On 0 to 10 Vdc control signal, the reference of the control signal is the

Common of the power supply of the SCR controller card.

• Use a Class 1 ( properly fused ) or Class 2, CSA or UL recognized transformer.

• 4 STAGE APPLICATION R850V-4

24 Vac contactor coils

C1

C2 C3 C4

V

S

C8

C7

C6

C5

C4

C3

C2

C1

C

POWER

1 2 3

R850V-4

2 3ON4

1

I

123

P

N

150

DELAY(s)

VR2

200

RATIO(%)

100

TEST

120

90

1 2 3ON4

CONTROL

60

30

T

U

REV.1

COM

JUNE 99

001-0102

Number
of stage

1
2
3
4

R850V-4 Control Switch

Switch #3 Switch #4

Off Off
On Off
Off On
On On

2