DriSteem Vapor-logic3 User manual

Vapor-logic 3
Humidifier Control System
Installation and
Operation Manual
®
VL3_IOM.pdf 1 11/19/2009 9:11:00 AM

VL3_IOM.pdf 2 11/19/2009 9:11:05 AM

DRI-STEEM Vapor-logic 3 *OTUBMMBUJPOBOE0QFSBUJPO.BOVBMt1BHFJ
Table of contents
IMPORTANT
Read and save these instructions.
Overview
Productoverview..........................................1
Summaryoffeatures.......................................2
Controlinputsignals.......................................3
TPmodulation............................................5
SSRmodulation ........................................... 6
Valve and burner modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Waterlevelcontrol—standardwatermodels.................. 8
Waterlevelcontrol—DI/ROmodels.........................9
Installation
Installing the keypad/display ...............................10
Maincontrolboardconnections............................11
GTSexpansionboardconnections..........................15
Vaporstreamexpansionboardconnections...................17
Installationchecklist ......................................18
Typicalinstallation........................................19
Generalwiringprocedures.................................20
Controlcabinetconnections................................22
Sensor device placement and humidity control overview .......25
Wiring sensor devices .....................................26
Configuration string programming..........................32
InteroperabilityusingLonTalk..............................34
Multiple-tank configurations ...............................42
Multiple-tank configuration string ......................50
Operation
Usingthekeypad.........................................52
Menustructureoverview ..................................54
Main menu screens:
Idlescreen ...........................................56
Statusscreen .........................................58
Control modes screen .................................59
Alarmsscreen........................................60
Faultmessages....................................61
SystemSetUpscreen..................................63
Adjustingsetpoint................................65
PID tuning.......................................66
VAV,tempcompcontroloperation..................70
Dewpointcontrol,tankpreheatoperation ...........71
Aquastat,freezeprotectionoperation................72
SDU/fan operation, sensor offsets ...................73
Automatic drain sequence (ADS) ...................74
End-of-seasondrain...............................76
Service interval, setting date and time ...............77
Diagnostics screen ....................................78
Reportsscreen........................................79
Start-upchecklist.........................................81
Troubleshooting..........................................84
Replacement parts .......................................101
Notes ................................................102
Warranty.........................................Backcover
VL3_IOM.pdf 3 11/19/2009 9:11:05 AM

1BHFJJt%3*45&&.7BQPSMPHJD 3 Installation and Operation Manual
VL3_IOM.pdf 4 11/19/2009 9:11:05 AM

DRI-STEEM Vapor-logic 3 *OTUBMMBUJPOBOE0QFSBUJPO.BOVBMt1BHF
1SPEVDUPWFSWJFX
Accurate, responsive microprocessor control
Vapor-logic
3 provides comprehensive control for DRI-STEEM
humidifiers. With extensive capabilities and easy-to-use keypad, the
Vapor-logic
3 efficiently controls all humidifier functions.
Navigating the keypad to adjust or review humidifier functions is an
intuitive process of walking through easily read screen menus.
You will find no other controller in the humidifier market able
to provide such functionality, ease of use, and accurate relative
humidity (RH) control.
Control options
t On-off control: Vapor-logic
3 uses a humidistat to enable
single-staged or multiple-staged electric outputs.
Expected accuracies: ± 5% to 7% RH
t Time proportioned (TP) control: Vapor-logic
3 directly reads
space RH and uses a proportional, integral, derivative (PID) loop
to vary the duty cycle of humidifier outputs to the solid state relay
(SSR) power controllers or contactors.
Expected accuracies:
– Contactor action: ± 2% to 4% RH
– SSR action: ± 1% to 3% RH
t Modulated control: Vapor-logic
3 directly reads space RH and
uses a PID loop to control modulating steam or hot water valves
(on STS or LTS) or GTS burners by providing a linear analog
signal to the combustion air blowers.
Expected accuracies: ± 2% to 5% RH
t Control signal by others: Vapor-logic
3 accepts an analog control
signal from another controller that directly determines the output
of the humidifier.
Expected accuracies: Determined by external control system
t LonTalk® interoperability: Allows communication with a
LonTalk building automation system using Standard Network
Variable Types (SNVTs or “snivits”).
VL3_IOM.pdf 5 11/19/2009 9:11:05 AM

1BHFt%3*45&&.7BQPSMPHJD 3 Installation and Operation Manual
Summary of features
t Self-diagnostic test at startup
t End-of-season automatic drain
t 3FBMUJNFDMPDL allows time-stamped alarm tracking and three
ways to program drain and flush cycles:
1. Usage (unit drains after a set number of pounds [kg] of water
cycle through)
2. Usage and interval (time) (unit drains at a preset time after a
set number of pounds [kg] of water cycle through)
3. At a preset interval (time)
t Keypad has a backlit display and features:
– Intuitive menu-driven access to all system functions
– Default screen for quick viewing of status and set points
– Data reports to track performance and efficiency
– System diagnostics and alarm tracking for troubleshooting
– Password protection of setup parameters
– Easy viewing in low light environments
– Three ways to mount the keypad:
1. Hand held (shipped with a 5' [1.5 m] cable)
2. Mounted on the side of the control cabinet or humidifier
shroud
3. Mounted remotely using a standard telephone plate. The
keypad can be located up to 500' (152 m) — the maximum
length of the keypad cable — from the controller board and
control cabinet.
t Tank temperature sensor, mounted on the evaporating chamber,
allows Vapor-logic
3 to provide:
– Over-temperature protection (on some models)
– Freeze protection
– Tank preheating, allowing rapid response to a call for
humidity
t Sensitivity to low conductivity water (important when using a
standard humidification system with low mineral content water)
t Single-controller platform; modular design
The Vapor-logic
3 controller is standard on most DRI-STEEM
humidifiers. The base configuration includes a main controller
board and keypad. Expansion modules increase capability and
allow DRI-STEEM humidifier systems to use the same controller
platform and keypad interface.
Summary of features
VL3_IOM.pdf 6 11/19/2009 9:11:05 AM

DRI-STEEM Vapor-logic 3 *OTUBMMBUJPOBOE0QFSBUJPO.BOVBMt1BHF
Control input signals
DRI-STEEM offers three control options for all its humidification
systems controlled by Vapor-logic
3 : on-off control, demand signal
control, and transmitter control.
On-off control
On-off control—the simplest control scheme—does exactly what its
name implies: the output device turns fully on, then fully off. Most
residential furnaces use this type of control.
The humidistat that controls the humidifier has a differential
between the on and off switch points. The differential is established
at a range sufficient to prevent output short cycling. In other
words, the humidity level has to fall below set point before the
humidistat closes and energizes the humidifier. Once the humidifier
is energized, the humidistat stays closed until the humidity is
above set point. This creates an operating range that prevents the
humidifier from running for very short periods of time.
In applications where there are multiple contactor outputs, such as
a Vaporstream humidifier, contactors for each heat stage are pulled
in one at a time with a one-second delay between them to prevent
a brownout condition. In applications with a variable output stage,
such as a GTS humidifier, the outputs are ramped up until they
reach 100%.
Demand signal control
With demand signal control, the Vapor-logic
3 controller provides
the output level that a master control signal calls for. This signal
can be generated either by a humidistat or by a building automation
system. The signal sent to the Vapor-logic
3 board is a modulating
signal (typically 4 to 20 mA or 0 to 10 VDC). Vapor-logic
3 responds
to this signal by producing a direct proportional output. In other
words, with a 4 to 20 mA signal, a command of 4 mA produces no
output. A command of 12 mA runs the humidifier at 50% demand,
and a command of 20 mA runs the humidifier at 100% demand.
With a humidistat provided by DRI-STEEM producing this signal,
the humidity set point is set at the humidistat. The keypad/display
then is used for maintaining and troubleshooting the humidification
system, with humidifier control stemming from the humidistat
itself. With a building automation system (BAS) providing the
signal, the humidity set point is established by the BAS, and the
humidifier responds to the BAS commands.
VL3_IOM.pdf 7 11/19/2009 9:11:05 AM

1BHFt%3*45&&.7BQPSMPHJD 3 Installation and Operation Manual
Transmitter control
With transmitter control, the Vapor-logic
3 board receives a linear
signal that corresponds to the actual humidity level measured
in the space being controlled. (With a transmitter provided by
DRI-STEEM, the signal is 4 to 20 mA, which corresponds to
0 to 100% RH). The Vapor-logic
3 controller employs an internal
PID loop that uses this humidity measurement along with a
user–defined humidity set point to calculate a demand level. This
demand level is the level at which the humidifier will run. For more
information on the PID control loop, refer to Page 66.
Control input signals, continued
VL3_IOM.pdf 8 11/19/2009 9:11:05 AM

DRI-STEEM Vapor-logic 3 *OTUBMMBUJPOBOE0QFSBUJPO.BOVBMt1BHF
51NPEVMBUJPO
TP modulation (electric humidifiers)
The standard form of modulation with an electric humidifier is time
proportioning (TP) modulation. With TP modulation, the outputs
cycle on and off at a certain rate to approximate humidifier demand
as the example below illustrates. To calculate the example, imagine
that each contactor represents 25% of the output of the humidifier.
With a 55% system demand, you need two full contactors plus 5/25
of a third contactor. Therefore, two contactors are full on and a
third contactor is on for 5/25 of 60 seconds, or 12 seconds.
Example
If a Vaporstream humidifier has four heat output stages (four
contactors) and a demand of 55%, two of the contactors are
energized all of the time; one contactor cycles on and off at a certain
rate, and one contactor is off. The rate at which the third contactor
cycles is determined by the demand and the heater cycle time.
Continuing with the example, if you have a heater cycle time of 60
seconds and a demand of 55%, the third contactor cycles at a rate of
12 seconds on and 48 seconds off.
To minimize wear on cycling contactors, Vapor-logic
3 keeps track
of the number of cycles on all contactors, and rotates the TP cycling
contactor to ensure that all contactors get equal wear. In addition,
to prevent short cycling, no contactor has a cycle time less than two
seconds or greater than the heater cycle time minus two seconds.
If system demand dictates that a contactor is on for less than a
second, the contactor does not energize. If the contactor is on
for between one and two seconds, the contactor energizes for the
minimum two-second period. Also, if a contactor is de-energized
for less than one second, it stays on. If a contactor is de-energized
for between one and two seconds, the contactor de-energizes for the
minimum two-second period.
These measures prevent short cycling of the contactors and extend
their life. On a TP system with contactors, the heater cycle time
is user adjustable and can be set from 30 seconds to 99 seconds
(default is 60 seconds) via the Vapor-logic
3 keypad/display.
TP modulation (gas humidifiers)
GTS burners provide TP modulation control when system
demand is low. See Page 7 for more information about gas burner
modulation.
VL3_IOM.pdf 9 11/19/2009 9:11:05 AM

1BHFt%3*45&&.7BQPSMPHJD 3 Installation and Operation Manual
SSR modulation
DRI-STEEM electric humidifiers are available with two basic
types of solid state relay (SSR) modulation: SSR modulation with
contactors and 100% SSR modulation.
SSR modulation with contactor sequence
On systems that employ SSR modulation with contactors, the
operation of the unit is the same as with TP modulation. In this
scenario, one of the cycling contactors is replaced with an SSR. The
SSR now is the device that carries out all of the cycling duties. The
contactors are always either on or off. Any needed TP cycling is
handled by the SSR stage.
This provides two distinct advantages over standard TP modulation.
First, an SSR can turn on and off much faster than a contactor can.
Therefore, as the unit modulates around a demand signal, tighter
control is achieved because the cycle time on an SSR system can be
as low as one second (factory set at two seconds). This means that
every two seconds, the controller can adjust the on and off times of
the SSR to closely track desired demand.
The second major advantage over standard TP modulation is
reliability. With a solid state device like an SSR, component wear
is almost nonexistent compared with an electromechanical device
such as a contactor. Therefore, with the SSR doing all of the heavy
cycling work, the life expectancy of the contactors is extended.
100% SSR modulation
The ultimate in electric humidifier modulation is 100% SSR
modulation. With this type of control, all heat stages are controlled
by SSRs. This allows the output of the humidifier to track the actual
demand closely because all heat stages now can cycle on and off at
the rapid SSR cycle rate.
With 100% SSR modulation, a contactor is wired in series with
the SSR devices as an additional safety feature. If an SSR fails, the
controller will de-energize the contactor, which will de-energize the
heaters.
VL3_IOM.pdf 10 11/19/2009 9:11:05 AM