Our customers have asked many questions about PMS Controllers. Here, we have assembled some of the more frequently asked questions that, we hope, will help to satisfy your own particular needs.
To make matters easier this section has been grouped into the four main areas that cover most of the queries that we receive. If you do not find an answer to your own question then please use the "Personal Query" feature at the bottom of the page.
Control covers points about what range of controls does PMS offer and what control do they give.
Connectivity shows how easy it may be to connect up a PMS Controller to any Hot Runner Tool
Availability shows which products are available Off-the-shelf and what are expected delivery times for complex machines.
Benefits covers the host of other little topics which answer Why should you choose PMS Controllers for your particular application.
Control
What is the difference between "Open" and "Closed" loop control?
How many zones can PMS Controllers regulate?
What is the control temperature range for PMS Controllers?
Can PMS Controller work at a distance?
What is the difference between "Open" and "Closed" loop control?
Closed-loop uses a thermocouple to read the nozzle temperature and provide
feedback to the controlling circuit. This effectively forms a control-loop
of action and reaction - the output power is dependent on the temperature
readings coming back from the sensor and regulated accordingly. Open-loop
control has no regulatory feedback, it just outputs a manually set power
value with no knowledge of what the resultant temperature is doing.
Open-loop, in practice, takes much longer to settle to the desired temperature
and is easily disrupted by injection, variations in the melt temperature,
mold cooling etc.. However it is available as a quick fix if a sensing
thermocouple fails. Closed-loop is much more responsive and adaptive.
When coming up to temperature, a closed-loop zone will initially apply
large amounts of power and then back off as it approaches the set point.
In open loop the power level is set to the final lower level and it can
take forever and a day to get up to molding temperature.
Closed-loop is frequently know as "Auto" mode and Open-loop is usually known as "Manual" mode.
How many zones can PMS Controllers regulate?
PMS Controllers are supplied in a wide range of controllers which accommodate a range of zones and offer different facilities.
| Model | Zones | Facilities |
|---|---|---|
| HL Series | 1, 2 or 4 zones | - a basic temperature controller. |
| HS Series | 2, 4 or 8 zones | - a temperature controller with power limiting |
| HRX Series | 4,6,8, or 12 zones | - a more advanced controller with limiting, alarms, tool memory and self diagnosis |
| HRC-A | 4,6,8 or 10 zones | - a modular controller with all the above facilities plus control card interchangability and up to two high-power zones. |
| HRC-E | from 4 to 40 zones | - our most popular modular controller. This is usually built to a customers specification and offers all the above facilities plus Pulse-Synch probe control, low voltage option. |
| HRC-C | up to 160 zones normal (although specials could expand on this further) | - our totally customisable unit which offers every facility and can be supplied with its own integral control display unit or remote consoles which offer even more flexibility |
| K-Series | available in 4 case sizes, that can accommdate up to 240 zones, in 60 zone steps | - a compact and cost-effective solution to almost any Hot Runner application. |
What is the control temperature range for PMS Controllers?
All PMS controllers offer infinite control over the range 0-400°C. Because of the unique way that PMS Controllers build a virtual model of their heating load, then the required temperature is reached in the minimum time with virtually no overshoot or deviation.
Can PMS Controller work at a distance?
What is "at a distance"?. All PMS Controllers come with a standard 2 or 3 metre loom (depending on model) and, at a price, these looms can be supplied in any almost any length. (Our record to date is 14 metres)
Some working situations call for completely remote working and there is a limit to how far you can extend wiring looms before cable resistance stops efficient working. In such cases then we offer HRC-C controllers with either LCD or Touch Screen consoles. By using this arrangement, you can site the consoles in a completely different part of the building. The LCD Console does offer some restrictions since the Data and Power cable are shared and if you need to use very remote working then you may need an auxiliary power supply.
To get even further away our "Touch Screen" console uses the Internet connections and you could use a second console in another country (if required) to control or interrogate any other "Touch Screen" console that was similarly connected.
Connectivity
What are PMS Wiring Standards - (will a PMS Hot Runner Controller be compatible with my machine)?
Because there is no "International Standard" yet available for Hot Runners controls, PMS have adopted their own simple wiring standard which uses the current standard colours with tri-rated cables.
The standard that we have adopted is common to several other manufacturers and where there may be differences all our machines can be supplied in any unique connection principal to match your own tools without the need for in-line "Change-over" connectors.
Availability
Are PMS Controllers available "Off-the-Shelf"?
PMS Controllers tend to fall into one of two families
- Standard controllers
- Customer configurable controllers
Our standard controllers run from the HL Series up to, and including, the HRX Series. Because these are all fabricated to the same internal standards then we always carry some which are ex-stock and which are immediately available. The HRC-A would also be a standard controller except for the optional 2-off high power zones so this unit may take a little longer to supply.
HRC-E, C and K Series Controllers tend to be much larger machines and are always
built to order. Depending on the complexity (and our current work load)
then you may have to wait 4 - 6 weeks for delivery on these custom controllers.
Benefits
Can PMS Controllers control other peripheral devices?
This rather depends on the particular device in mind. However Newer PMS Controllers that are supplied with the "Touch Screen" Console have the ability to control and/or monitor other peripheral devices.
Our "Touch Screen" Console can communicate with outside devices using both OMRON and SPI protocols. More recently we have extended the control range so that this console can set and control external water chillers where there is a two-way interface. Other devices, such as hoppers, conveyors etc. may offer only one-way communication and in this situation the Console can be adapted to display the information received.
Do PMS Controllers need recalibration?
Because of their unique digital design with CPU Control all our controllers need no further calibration once they have left the factory.
If you have any more questions...
If you have any further queries about PMS Hot Runner Controllers then please do not hesitate to contact us directly..
| Write to: |
PMS Systems Ltd |
| Telephone | +44 (0)1432 265768 |
| Fax | +44 (0)1432 263782 |
| pms@pmssystems.com |