KELCO T20 Installation manual

KELCO T20 TIMER
INSTALLATION & PROGRAMMING INSTRUCTIONS
KELCO Engineering Pty Ltd
Sydney Australia
www.kelco.com.au

Table Of Contents
Warning Symbols Explained.......................................................... 1
Important Safety Instructions......................................................... 2
Overview........................................................................................ 3
Installing the T20........................................................................... 4
Electrical........................................................................................ 5
Blackout or Brownout.................................................................... 6
Cable Gland Assembly................................................................... 7
The Heavy Duty (HD) Terminal...................................................... 8
Electrical Limitations...................................................................... 9
Circuit Diagrams............................................................................ 10
The 12VDC T20 Timer................................................................... 14
T20 Controls and Terminals........................................................... 15
Remote Flow Switch Input............................................................. 17
Suitable Flow Switches.................................................................. 19
Purging the T20............................................................................. 20
Programming the T20 Timer.......................................................... 21
Basic Operation............................................................................. 22
T20 Table of Limitations................................................................. 23
Advanced Functions...................................................................... 24
Batch Control................................................................................. 25
Delayed Restarting........................................................................ 26
Cyclic Running............................................................................... 27
Anti-Cycling.................................................................................... 28
Burst Pipe Detector........................................................................ 29
LCD Screen Backlight, Program Lock.......................................... 30
Program Lock................................................................................ 30
Maintenance.................................................................................. 30
Warranty......................................................................................... 31
Page

This symbol is intended to alert the user
to the presence of important operating
and maintenance instructions in the lit-
erature accompanying the T20 timer
WARNING
This symbol is intended to alert the user
to the presence of un-insulated “danger-
ous voltage” within the timer’s enclo-
sure that may be of sufcient magnitude
to constitute a risk of severe electric
shock.
WARNING
1

IMPORTANT SAFETY
INSTRUCTIONS
• Read these instructions.
• Keep these instructions.
• Heed all warnings.
• Follow all instructions.
• Do not allow water to enter this timer.
• Install this timer per the manufacturer’s instructions.
• Do not install this timer near any heat source such as
radiators, gas heaters, stoves or any other appliance that produces heat.
• Do not modify this timer in any way.
• Do not drill holes in this timer’s casing.
• Refer all installation and servicing to qualied service personnel.
• Servicing is required when the timer has been damaged in any way,
such as submerged in water, exposed to re, dropped or objects dropped
on it. Exposed to moisture or water when the timer’s lid is removed.
Please read these installation and operating in-
structions carefully and fully before installing or
servicing this timer. The T20 is a mains voltage
device. Death or serious injury may result if this
product is not correctly installed and operated.
WARNING
2

Overview
When connected to an external ow switch the T20 timer provides a pumping
system with a set of useful time and ow based functions. The T20 can be con-
gured in a variety of ways to control the pump and to protect it. It can be set to
start a pump in spite of an initial lack of ow and to then do no more than protect
it against loss of ow. The T20 can also be programmed to simulate a complex
pump control panel. This document sets out in detail the installation and functions
of the T20 timer and some of the main ways in which it can be used in pumping
and irrigation systems.
Without its lid in place the T20 timer is not water
resistant and presents a potential shock hazard.
Take great care not to splash water onto the T20
when the lid is not in place. Always replace the
lid and fully tighten its 6 securing screws imme-
diately after any changes to the timer’s settings
are made.
WARNING
3
INSTALLING THE T20 TIMER
Location
Where possible install this timer in a location that is sheltered from direct expo-
sure to the weather. The T20 is weatherproof and is supplied with a protective clip
on cover. However, to ensure a long reliable life we recommend it be protected
from direct exposure to the sun and rain. Intense sun light will eventually cause
discolouration and degradation of the timer’s housing. It is therefore advisable to
protect the timer from the weather if possible.
The T20 timer should be installed on a wall or on a bracket attached to a pump
or its pipework. Where large pump motors are to be directly controlled, mount the
T20 as close as practical to the supply and pump to keep heavy cable runs to a
minimum.

4
Installing the T20
The T20 timer is supplied as two separate assemblies, the wall mounting bracket
and the electrical housing. The mounting bracket should be installed rst by
securing it to a wall or to a plate attached to the pipework or pump. The drilling
pattern is shown below.
60mm
74mm
Attach the electrical housing to the wall bracket by engaging the two toes on the
bracket into the two notches in the retainer plate on the underside of the electri-
cal housing. Secure the electrical housing to the wall bracket using the large hex
headed red bolt supplied in the kit. Tighten the red bolt using a broad bladed
screwdriver or small socket wrench. Do not overtighten it.
4 X 6mm
Holes

Electrical
All electrical work associated with the T20 must
be carried out by qualied electrical personnel
and all electrical work must conform to AS/NZ
standards and to local wiring rules. For mains
voltage applications we recommend the sup-
ply to the T20 be isolated by an RCD that has a
maximum trip current of 30mA.
WARNING
Introduction
The T20 timer is designed to directly control single-phase pump motors to 3.75kW.
No interposing contactor is required for such applications. If a supply neutral or
transformer is available, the timer can also be used to control 3 phase pump mo-
tors via an appropriate interposing contactor that has a suitable coil voltage.
The T20 timer requires a 220V to 240V AC 50Hz supply when operated from the
mains. It can also be operated from an 18 to 24V AC or DC supply by utilising the
low voltage active terminal LV and common neutral terminal N, see the included
wiring diagrams. When operated from a low voltage DC supply the terminals LV
and neutral N are not polarity sensitive. The T20 timer requires a stable supply
voltage in order to operate correctly. Pay particular attention to cable sizes, and
ensure cables are adequate for the specic pump motor load. This is particularly
important where long cable runs are to be used in the installation. If the voltage
drop associated with the starting of the pump motor is excessive the T20 will au-
tomatically reset and this may cause the pump to jog. Jogging can snap the main
spindle of a pump very easily, so please take all precautions to ensure the voltage
supply to the T20 is stable and that the current carrying capacity of the cable used
is adequate for the job.
5

Brownout Or Blackout
If a blackout or brownout occurs the T20 timer will not retain memory of where in
its run or stop cycles it may have been. When power resumes, the T20 will reboot
and resume running. A manual reboot can be done at any time by pressing the
timer’s reset button.
The T20 timer derives low voltage for its opera-
tion from a non-isolated reactance power sup-
ply (not through an isolated transformer). All
external devices connected to the T20 must be
earthed and must be regarded as operating at
full mains potential. For all mains voltage ap-
plications we recommend the supply to the T20
be isolated by an RCD that has a maximum trip
current of 30mA.
WARNING
Cables
The T20 timer has 3 X M20 cable glands. As supplied the cable glands are
blanked off. To use the glands rst punch out the blanking barriers using a suit-
able punch. The cable glands can accept cable from 7 to 9mm diameter. See
attached sketch for assembling the cable gland components. The timer is sup-
plied with a set of steel crimp rings. The crimp rings are to provide strain relief for
the timers cables. To use the crimps, place one on the cable approximately 4mm
below the end to the cable’s outer sheathing. Crimp the two ears of the ring at
using bull nosed pliers. Pull the cable back through the cable gland until the crimp
ring’s ears are fully engaged in the two slots in the gland housing.
6

Relays
The T20 timer houses 2 relays. The contacts of both relays are voltage free and
are normally open. The relays are marked Relay 1 and Relay 2 on the terminal
block. Relay 1 is the primary relay and is used to control the pump motor. It has
an electrical rating of 30 Amps (resistive) at 240VAC. Relay 2 is a 16 Amp (resis-
tive) 240VAC rated relay and is used for actuating an external alarm. The relays
built into the T20 timer are not suitable for the direct control of DC motors.
7
Cable Gland Assembly

The HD (Heavy Duty) Terminal
The HD terminal must be left unused or only
ever be linked to the relay terminal Relay 1 Nor-
mally Open. It must never be used for any other
purpose and it must never be connected to any
external device. Under no circumstances con-
nect the HD terminal to the terminals of Relay 2.
The HD terminal must be regarded as live at all
times and at full mains potential
WARNING
The T20 timer contains a solid-state switch (HD Heavy Duty drive) that can be
used to protect the contacts of Relay 1 by eliminating the destructive arcing
caused by the starting and stopping of pump motors. The solid-state switch is
accessible from the HD (Heavy Duty) terminal on the terminal block. We recom-
mend the HD drive be used whenever the timer is used to directly control a pump
motor. The HD drive should not be used when the T20 is connected to external
timers, contactors, relays or to any other external device where voltage free con-
tacts are required. It is strictly intended for the direct control of highly inductive
AC motor loads. The HD terminal and the timer’s built in relays must never be
connected to a DC motor under any circumstances.
When the HD terminal is linked to the terminal Relay 1 Normally Open, the HD
drive in effect parallels a 40Amp solid state switch across the relay’s normally
open contacts. This increases the momentary current carrying capacity of the
relay’s contacts to well over 70 Amps. The solid state HD drive is only activated
for a short period when the pump starts and stops. It effectively handles the high
inrush current associated with the pump starting, and it provides a current path for
the destructive back EMF associated with the pump motor stopping.
To use the HD drive place a heavy link wire, 1.0mm or 1.5mm Sq between the HD
terminal and the Normally Open terminal of Relay 1.
8